{"id":17649,"date":"2018-06-29T11:36:06","date_gmt":"2018-06-29T06:06:06","guid":{"rendered":"http:\/\/mycbseguide.com\/blog\/?p=17649"},"modified":"2019-01-18T18:17:15","modified_gmt":"2019-01-18T12:47:15","slug":"cbse-question-paper-2018-class-12-chemistry","status":"publish","type":"post","link":"https:\/\/mycbseguide.com\/blog\/cbse-question-paper-2018-class-12-chemistry\/","title":{"rendered":"CBSE Question Paper 2018 class 12 Chemistry"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_76 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/mycbseguide.com\/blog\/cbse-question-paper-2018-class-12-chemistry\/#Previous_Year_Question_Papers_-Download_Free_PDF\" >Previous Year Question Papers -Download Free PDF<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/mycbseguide.com\/blog\/cbse-question-paper-2018-class-12-chemistry\/#Class_12_Chemistry_list_of_chapters\" >Class 12 Chemistry list of chapters<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/mycbseguide.com\/blog\/cbse-question-paper-2018-class-12-chemistry\/#CBSE_Question_Paper_2018_class_12_Chemistry\" >CBSE Question Paper 2018 class 12 Chemistry<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/mycbseguide.com\/blog\/cbse-question-paper-2018-class-12-chemistry\/#Chemistry_Question_Paper_2018_with_solution\" >Chemistry Question Paper 2018 with solution<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/mycbseguide.com\/blog\/cbse-question-paper-2018-class-12-chemistry\/#Previous_Year_Question_Paper_for_class_12\" >Previous Year Question Paper for class 12<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"title\"><span class=\"ez-toc-section\" id=\"Previous_Year_Question_Papers_-Download_Free_PDF\"><\/span>Previous Year Question Papers -Download Free PDF<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong>CBSE Question Paper 2018 class 12 Chemistry<\/strong>\u00a0conducted by Central Board of Secondary Education, New Delhi in the month of March 2018. CBSE previous year question papers with solution are available in myCBSEguide mobile app and cbse guide website. The Best CBSE App for students and teachers is myCBSEguide which provides complete study material and practice papers to cbse schools in India and abroad.<\/p>\n<p style=\"text-align: center;\"><strong>CBSE Question Paper 2018 class 12 Chemistry<\/strong><\/p>\n<p style=\"text-align: center;\"><strong><a class=\"button\" href=\"https:\/\/mycbseguide.com\/dashboard\/#\/home\">Download as PDF<\/a><\/strong><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignright\" src=\"https:\/\/media-mycbseguide.s3.ap-south-1.amazonaws.com\/images\/blog\/Class%2012%20Chemistry%20Book%20in%20English.jpg\" alt=\"CBSE Question Paper 2018 class 12 Chemistry\" width=\"112\" height=\"143\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Class_12_Chemistry_list_of_chapters\"><\/span>Class 12 Chemistry list of chapters<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ol>\n<li>The Solid State<\/li>\n<li>Solutions<\/li>\n<li>Electrochemistry<\/li>\n<li>Chemical Kinetics<\/li>\n<li>Surface Chemistry<\/li>\n<li>General Principles and Processes of Isolation of Elements<\/li>\n<li>The p-Block Elements<\/li>\n<li>The d and f Block Elements<\/li>\n<li>Coordination Compounds<\/li>\n<li>Haloalkanes and Haloarenes<\/li>\n<li>Alcohols, Phenols and Ethers<\/li>\n<li>Aldehydes, Ketones and Carboxylic Acids<\/li>\n<li>Amines<\/li>\n<li>Biomolecules<\/li>\n<li>Polymers<\/li>\n<li>Chemistry in Everyday life<\/li>\n<\/ol>\n<h2><span class=\"ez-toc-section\" id=\"CBSE_Question_Paper_2018_class_12_Chemistry\"><\/span>CBSE Question Paper 2018 class 12 Chemistry<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong>Time allowed: 3 hours<br \/>\nMaximum Marks: 70<\/strong><\/p>\n<p><strong>General Instructions:<\/strong><\/p>\n<ol start=\"1\">\n<li>All questions are compulsory.<\/li>\n<li>Questions number 1 to 5 are very short answer questions and carry 1 mark each.<\/li>\n<li>Questions number 6 to 10 are short answer questions and carry 2 marks each.<\/li>\n<li>Questions number 11 to 22 are also short answer questions and carry 3 marks each.<\/li>\n<li>Question number 23 is a value based question and carries 4 marks.<\/li>\n<li>Questions number 24 to 26 are long answer questions and carry 5 marks each.<\/li>\n<li>Use log tables, if necessary. Use of calculators is not allowed.<\/li>\n<\/ol>\n<hr \/>\n<ol start=\"1\">\n<li><strong>Analysis shows that FeO has a non-stoichiometric composition with formula Fe<sub>0\u00b795<\/sub>O. Give reason.<br \/>\nAns.<\/strong> Shows metal deficiency defect \/ It is a mixture of Fe<sup>2+<\/sup> and Fe<sup>3+<\/sup>\/Some Fe<sup>2+<\/sup> ions are replaced by Fe<sup>3+<\/sup> \/ Some of the ferrous ions get oxidised to ferric ions.<\/li>\n<li><strong>CO (g) and H<sub>2<\/sub> (g) react to give different products in the presence of different catalysts. Which ability of the catalyst is shown by these reactions?<br \/>\nAns.<\/strong> Selectivity of a catalyst<\/li>\n<li><strong>Write the coordination number and oxidation state of Platinum in the complex [Pt(en)<sub>2<\/sub>Cl<sub>2<\/sub>].<br \/>\nAns.<\/strong> Coordination Number = 6, Oxidation State = +2<\/li>\n<li><strong>Out of chlorobenzene and benzyl chloride, which one gets easily hydrolysed by aqueous NaOH and why?<br \/>\nAns.<\/strong> Benzyl chloride; Due to resonance, stable benzyl carbocation is formed<\/li>\n<li><strong>Write the IUPAC name of the following:<br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images01.png\" alt=\"CBSE Question Paper 2018 class 12 Chemistry\" width=\"201\" height=\"106\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images01.png\" \/><br \/>\nAns.<\/strong> 3,3 &#8211; Dimethylpentan-2-ol<\/li>\n<li><strong>Calculate the freezing point of a solution containing 60 g of glucose (Molar mass = 180 g mol<sup>-1<\/sup>) in 250 g of water.<br \/>\n(K<sub>f<\/sub> of water = 1\u00b786 K kg mol<sup>-1<\/sup>)<br \/>\nAns.<\/strong> <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"40\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%5C%5CDelta%20%7BT_f%7D%20%3D%20%7BK_f%7Dm%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\Delta {T_f} = {K_f}m\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"39\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20%3D%20%7BK_f%7D%5C%5Cfrac%7B%7B%7Bw_z%7D%20%5C%5Ctimes%201000%7D%7D%7B%7B%7BM_2%7D%20%5C%5Ctimes%20%7Bw_1%7D%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? = {K_f}\\frac{{{w_z} \\times 1000}}{{{M_2} \\times {w_1}}}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"38\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20%3D%20%5C%5Cfrac%7B%7B1.86%20%5C%5Ctimes%2060%20%5C%5Ctimes%201000%7D%7D%7B%7B180%20%5C%5Ctimes%20250%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? = \\frac{{1.86 \\times 60 \\times 1000}}{{180 \\times 250}}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n= 2.48 K<br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"37\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%5C%5CDelta%20%7BT_f%7D%20%3D%20%7BT_f%7D%20-%20%7BT_f%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\Delta {T_f} = {T_f} - {T_f}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n2.48 = 273.15 &#8211; T<sub>f<\/sub><br \/>\nT<sub>f<\/sub> = 270.67 K\/270.52 K\/-2.48 <sup>o<\/sup>C<\/li>\n<li><strong>For the reaction<br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"36\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D2%7BN_2%7D%7BO_5%7D(g)%20%5C%5Cto%204N%7BO_2%7D(g)%20%2B%20%7BO_2%7D(g)%2C%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?2{N_2}{O_5}(g) \\to 4N{O_2}(g) + {O_2}(g),\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\nthe rate of formation of NO<sub>2<\/sub> (g) is <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"35\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%202.8%20%5C%5Ctimes%20%7B10%5E%7B%20-%203%7D%7DM%7Bs%5E%7B%20-%201%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? 2.8 \\times {10^{ - 3}}M{s^{ - 1}}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span>. Calculate the rate of disappearance of N<sub>2<\/sub>O<sub>5<\/sub> (g).<br \/>\nAns.<\/strong><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"34\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7DRate%20%3D%20%5C%5Cfrac%7B1%7D%7B4%7D%5C%5Cfrac%7B%7B%5C%5CDelta%20(N%7Bo_2%7D)%7D%7D%7B%7B%5C%5CDelta%20(t)%7D%7D%20%3D%20-%20%5C%5Cfrac%7B1%7D%7B2%7D%5C%5Cfrac%7B%7B(%7BN_2%7D%7BO_5%7D)%7D%7D%7B%7B%5C%5CDelta%20(t)%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?Rate = \\frac{1}{4}\\frac{{\\Delta (N{o_2})}}{{\\Delta (t)}} = - \\frac{1}{2}\\frac{{({N_2}{O_5})}}{{\\Delta (t)}}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"33\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%5C%5Cfrac%7B1%7D%7B4%7D(2.8%20%5C%5Ctimes%20%7B10%5E%7B%20-%203%7D%7D)%20%3D%20-%20%5C%5Cfrac%7B1%7D%7B2%7D%5C%5Cfrac%7B%7B%5C%5CDelta%20(%7BN_2%7D%7BO_5%7D)%7D%7D%7B%7B%5C%5CDelta%20(t)%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\frac{1}{4}(2.8 \\times {10^{ - 3}}) = - \\frac{1}{2}\\frac{{\\Delta ({N_2}{O_5})}}{{\\Delta (t)}}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\nRate of disappearance of N<sub>2<\/sub>O<sub>5<\/sub> <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"32\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%5C%5Cleft(%20%7B%20-%20%5C%5Cfrac%7B%7B%5C%5CDelta%20(%7BN_2%7D%7BO_5%7D)%7D%7D%7B%7B%5C%5CDelta%20(t)%7D%7D%7D%20%5C%5Cright)%20%3D%201.4%20%5C%5Ctimes%20%7B10%5E%7B%20-%203%7D%7DM%2Fs%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\left( { - \\frac{{\\Delta ({N_2}{O_5})}}{{\\Delta (t)}}} \\right) = 1.4 \\times {10^{ - 3}}M\/s\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n(Deduct half mark if unit is wrong or not written)<\/li>\n<li><strong>Among the hydrides of Group-15 elements, which have the<\/strong>\n<ol start=\"1\">\n<li><strong>lowest boiling point?<\/strong><\/li>\n<li><strong>maximum basic character?<\/strong><\/li>\n<li><strong>highest bond angle?<\/strong><\/li>\n<li><strong>maximum reducing character?<\/strong><\/li>\n<\/ol>\n<p><strong>Ans.<\/strong><\/p>\n<ol start=\"1\">\n<li>PH<sub>3<\/sub><\/li>\n<li>NH<sub>3<\/sub><\/li>\n<li>NH<sub>3<\/sub><\/li>\n<li>BiH<sub>3<\/sub><\/li>\n<\/ol>\n<\/li>\n<li><strong>How do you convert the following?<\/strong>\n<ol start=\"1\">\n<li><strong>Ethanal to Propanone<\/strong><\/li>\n<li><strong>Toluene to Benzoic acid <\/strong><strong>OR<\/strong><\/li>\n<\/ol>\n<p><strong> Account for the following: <\/strong><\/p>\n<ol start=\"1\">\n<li><strong>Aromatic carboxylic acids do not undergo Friedel-Crafts reaction.<\/strong><\/li>\n<li><strong>pK<sub>a<\/sub> value of 4-nitrobenzoic acid is lower than that of benzoic acid.<\/strong><\/li>\n<\/ol>\n<p><strong> Ans. <\/strong><\/p>\n<ol start=\"1\">\n<li><strong><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"31\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7DC%7BH_3%7DCHO%5C%5Cxrightarrow%7B%7B(i)C%7BH_3%7DMgBr%2CDry%5C%5C%3Bether(ii)%7BH_2%7DO%2F%7BH%5E%20%2B%20%7D%7D%7D%20%5C%5C%5C%5C%20C%7BH_3%7DCH(OH)C%7BH_3%7D%5C%5Cxrightarrow%7B%7BCr%7BO_3%7D%7D%7DC%7BH_3%7DCOC%7BH_3%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?C{H_3}CHO\\xrightarrow{{(i)C{H_3}MgBr,Dry\\;ether(ii){H_2}O\/{H^ + }}} \\\\ C{H_3}CH(OH)C{H_3}\\xrightarrow{{Cr{O_3}}}C{H_3}COC{H_3}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><\/strong><\/li>\n<li><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images06.png\" alt=\"CBSE Question Paper 2018 class 12 Chemistry\" width=\"328\" height=\"59\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images06.png\" \/><strong>OR<\/strong><\/li>\n<\/ol>\n<ol start=\"1\">\n<li><strong>b<\/strong>ecause the carboxyl group is deactivating and the catalyst aluminium chloride (Lewis acid) gets bonded to the carboxyl group<\/li>\n<li>Nitro group is an electron withdrawing group (-I effect) so it stabilises the carboxylate anion and strengthens the acid \/ Due to the presence of an electron withdrawing Nitro group (-I effect).<\/li>\n<\/ol>\n<\/li>\n<li><strong>Complete and balance the following chemical equations:<\/strong>\n<ol start=\"1\">\n<li><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"30\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7DF%7Be%5E%7B2%20%2B%20%7D%7D%20%2B%20MnO_4%5E%20-%20%2B%20%7BH%5E%20%2B%20%7D%20%5C%5Cto%20%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?F{e^{2 + }} + MnO_4^ - + {H^ + } \\to \" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><\/li>\n<li><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"29\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7DMnO_4%5E%20-%20%2B%20%7BH_2%7DO%20%2B%20%7BI%5E%20-%20%7D%20%5C%5Cto%20%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?MnO_4^ - + {H_2}O + {I^ - } \\to \" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><\/li>\n<\/ol>\n<p><strong>Ans.<\/strong><\/p>\n<ol start=\"1\">\n<li><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"28\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D5F%7Be%5E%7B2%20%2B%20%7D%7D%20%2B%20Mn%7BO_4%7D%20%2B%208%7BH%5E%20%2B%20%7D%20%5C%5Cto%20M%7Bn%5E%7B2%20%2B%20%7D%7D%20%2B%204%7BH_2%7DO%20%2B%205F%7Be%5E%7B3%20%2B%20%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?5F{e^{2 + }} + Mn{O_4} + 8{H^ + } \\to M{n^{2 + }} + 4{H_2}O + 5F{e^{3 + }}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><\/li>\n<li><span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"27\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D2MnO_4%5E%20-%20%2B%20%7BH_2%7DO%20%2B%20%7BI%5E%20-%20%7D%20%5C%5Cto%202Mn%7BO_2%7D%20%2B%202O%7BH%5E%7B%20-%7D%7D%20%2B%20IO_3%5E%20-%20%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?2MnO_4^ - + {H_2}O + {I^ - } \\to 2Mn{O_2} + 2O{H^{ -}} + IO_3^ - \" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><\/li>\n<\/ol>\n<\/li>\n<li><strong>Give reasons for the following:<\/strong>\n<ol start=\"1\">\n<li><strong>Measurement of osmotic pressure method is preferred for the determination of molar masses of macromolecules such as proteins and polymers.<\/strong><\/li>\n<li><strong>Aquatic animals are more comfortable in cold water than in warm water.<\/strong><\/li>\n<li><strong>Elevation of boiling point of 1 M KCl solution is nearly double than that of 1 M sugar solution.<\/strong><\/li>\n<\/ol>\n<p><strong>Ans.<\/strong><\/p>\n<ol start=\"1\">\n<li>As compared to other colligative properties, its magnitude is large even for very dilute solutions\/macromolecules are generally not stable at higher temperatures and polymers have poor solubility\/pressure measurement is around the room temperature and the molarity of the solution is used instead of molality.<\/li>\n<li>Because oxygen is more soluble in cold water or at low temperature.<\/li>\n<li>Due to dissociation of KCl \/ KCl (aq) <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"26\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20%5C%5Cto%20%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? \\to \" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span> K<sup>+<\/sup> + Cl<sup>&#8211;<\/sup>, i is nearly equal to 2<\/li>\n<\/ol>\n<\/li>\n<li><strong>An element \u2018X\u2019 (At. mass = 40 g mol<sup>-1<\/sup>) having f.c.c. structure has unit cell edge length of 400 pm. Calculate the density of \u2018X\u2019 and the number of unit cells in 4 g of \u2018X\u2019.<\/strong> <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"25\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20(%7BN_A%7D%20%3D%206.022%20%5C%5Ctimes%20%7B10%5E%7B23%7D%7Dmo%7Bl%5E%7B%20-%201%7D%7D)%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? ({N_A} = 6.022 \\times {10^{23}}mo{l^{ - 1}})\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span>.<br \/>\n<strong>Ans.<\/strong> <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"24\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7Dd%20%3D%20%5C%5Cfrac%7B%7BzM%7D%7D%7B%7B%7Ba%5E3%7D%7BN_A%7D%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?d = \\frac{{zM}}{{{a^3}{N_A}}}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"23\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20%3D%20%5C%5Cfrac%7B%7B4%20%5C%5Ctimes%2040%7D%7D%7B%7B%7B%7B(4%20%5C%5Ctimes%20%7B%7B10%7D%5E%7B%20-%208%7D%7D)%7D%5E3%7D%20%5C%5Ctimes%206.022%20%5C%5Ctimes%20%7B%7B10%7D%5E%7B23%7D%7D%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? = \\frac{{4 \\times 40}}{{{{(4 \\times {{10}^{ - 8}})}^3} \\times 6.022 \\times {{10}^{23}}}}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n= 4.15 g\/cm<sup>3<\/sup><br \/>\nNo of unit cells = total no of atoms \/4<br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"22\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20%3D%20%5B%5C%5Cfrac%7B4%7D%7B%7B40%7D%7D%20%5C%5Ctimes%206.022%20%5C%5Ctimes%20%7B10%5E%7B23%7D%7D%5D%2F4%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? = [\\frac{4}{{40}} \\times 6.022 \\times {10^{23}}]\/4\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"21\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20%3D%201.5%20%5C%5Ctimes%20%7B10%5E%7B22%7D%7D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? = 1.5 \\times {10^{22}}\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><\/li>\n<li><strong>A first order reaction is 50% completed in 40 minutes at 300 K and in 20 minutes at 320 K. Calculate the activation energy of the reaction. (Given : log 2 = 0\u00b73010, log 4 = 0\u00b76021, R = 8\u00b7314 JK<sup>-1<\/sup> mol<sup>-1<\/sup>).<\/strong><br \/>\n<strong>Ans.<\/strong> k<sub>2<\/sub> = 0.693\/20,<br \/>\nk<sub>1<\/sub> = 0.693\/40<br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"20\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%5C%5Clog%20%5C%5Cfrac%7B%7B%7Bk_2%7D%7D%7D%7B%7B%7Bk_1%7D%7D%7D%20%3D%20%5C%5Cfrac%7B%7B%7BE_a%7D%7D%7D%7B%7B2.303R%7D%7D%5B%5C%5Cfrac%7B1%7D%7B%7B%7BT_1%7D%7D%7D%20-%20%5C%5Cfrac%7B1%7D%7B%7B%7BT_2%7D%7D%7D%5D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\log \\frac{{{k_2}}}{{{k_1}}} = \\frac{{{E_a}}}{{2.303R}}[\\frac{1}{{{T_1}}} - \\frac{1}{{{T_2}}}]\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\n<span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"19\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%5C%5Clog%202%20%3D%20%5C%5Cfrac%7B%7B%7BE_a%7D%7D%7D%7B%7B2.303%20%5C%5Ctimes%208.314%7D%7D%5B%5C%5Cfrac%7B%7B320%20-%20300%7D%7D%7B%7B320%20%5C%5Ctimes%20300%7D%7D%5D%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi?\\log 2 = \\frac{{{E_a}}}{{2.303 \\times 8.314}}[\\frac{{320 - 300}}{{320 \\times 300}}]\" alt=\"CBSE Question Paper 2018 class 12 Chemistry\" width=\"236\" height=\"36\" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span><br \/>\nEa = 27663.8 J\/mol or 27.66 kJ\/mol<\/li>\n<li><strong>What happens when<\/strong>\n<ol start=\"1\">\n<li><strong>a freshly prepared precipitate of Fe(OH)<sub>3<\/sub> is shaken with a small amount of FeCl<sub>3<\/sub> solution ? <\/strong><\/li>\n<li><strong>persistent dialysis of a colloidal solution is carried out ? <\/strong><\/li>\n<li><strong>an emulsion is centrifuged?<\/strong><\/li>\n<\/ol>\n<p><strong> Ans.<\/strong><\/p>\n<ol start=\"1\">\n<li>Peptisation occurs \/ Colloidal solution of Fe(OH)<sub>3<\/sub> is formed<\/li>\n<li>Coagulation occurs<\/li>\n<li>Demulsification or breaks into constituent liquids<\/li>\n<\/ol>\n<\/li>\n<li><strong>Write the chemical reactions involved in the process of extraction of Gold. Explain the role of dilute NaCN and Zn in this process.<br \/>\nAns.<\/strong>4Au(S) + 8CN<sup>&#8211;<\/sup>(aq) + 2H<sub>2<\/sub>O(aq) + O<sub>2<\/sub>(g) <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"18\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20%5C%5Cto%20%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? \\to \" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span> 4[Au(CN)<sub>2<\/sub>]<sup>&#8211;<\/sup>(aq) + 4OH<sup>&#8211;<\/sup>(aq)<br \/>\n2[Au(CN)<sub>2<\/sub>]<sup>&#8211;<\/sup>(aq) + Zn(s) <span class=\"cke_widget_wrapper cke_widget_inline cke_widget_selected\" tabindex=\"-1\" contenteditable=\"false\" data-cke-widget-wrapper=\"1\" data-cke-filter=\"off\" data-cke-display-name=\"math\" data-cke-widget-id=\"17\"><span class=\"math-tex cke_widget_element\" data-cke-survive=\"1\" data-cke-widget-data=\"%7B%22math%22%3A%22%7Btex%7D%20%5C%5Cto%20%7B%2Ftex%7D%22%2C%22classes%22%3A%7B%22math-tex%22%3A1%7D%7D\" data-cke-widget-upcasted=\"1\" data-cke-widget-keep-attr=\"0\" data-widget=\"mathjaxlatex\"><img decoding=\"async\" src=\"https:\/\/elpiscart.com\/cgi-bin\/mathtex.cgi? \\to \" \/><\/span><img decoding=\"async\" class=\"cke_reset cke_widget_mask\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" \/><span class=\"cke_reset cke_widget_drag_handler_container\"><img loading=\"lazy\" decoding=\"async\" class=\"cke_reset cke_widget_drag_handler\" title=\"Click and drag to move\" draggable=\"true\" src=\"data:image\/gif;base64,R0lGODlhAQABAPABAP\/\/\/wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==\" width=\"15\" height=\"15\" data-cke-widget-drag-handler=\"1\" \/><\/span><\/span> 2Au(S) + [Zn(CN)<sub>4<\/sub>]<sup>2-<\/sup> (aq)<br \/>\nNaCN leaches gold\/NaCN acts as a leacing agent \/ complexing agent Zn acts as reducing agent \/ Zn displaces gold.<\/li>\n<li><strong>Give reasons :<\/strong>\n<ol start=\"1\">\n<li><strong>E<sup>o<\/sup> value for Mn<sup>3+<\/sup>\/Mn<sup>2+<\/sup> couple is much more positive than that for Fe<sup>3+<\/sup>\/Fe<sup>2+<\/sup>.<\/strong><\/li>\n<li><strong>Iron has higher enthalpy of atomization than that of copper.<\/strong><\/li>\n<li><strong>Sc<sup>3+<\/sup> is colourless in aqueous solution whereas Ti<sup>3+<\/sup> is coloured.<\/strong><\/li>\n<\/ol>\n<p><strong> Ans.<\/strong><\/p>\n<ol start=\"1\">\n<li>The comparatively high value for Mn shows that Mn<sup>2+<\/sup>(d<sup>5<\/sup>) is particularly stable \/ Much larger third ionisation energy of Mn (where the required change is from d<sup>5<\/sup> to d<sup>4<\/sup>)<\/li>\n<li>Due to higher number of unpaired electrons.<\/li>\n<li>Absence of unpaired d- electron in Sc<sup>3+<\/sup> whereas in Ti<sup>3+<\/sup> there is one unpaired electron or Ti<sup>3+ <\/sup>shows d-d transition.<\/li>\n<\/ol>\n<\/li>\n<li>\n<ol start=\"1\">\n<li><strong>Identify the chiral molecule in the following pair:<br \/>\n<img decoding=\"async\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images02.png\" alt=\"\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images02.png\" \/><\/strong><\/li>\n<li><strong>Write the structure of the product when chlorobenzene is treated with methyl chloride in the presence of sodium metal and dry ether.<\/strong><\/li>\n<li><strong>Write the structure of the alkene formed by dehydrohalogenation of 1-bromo-1-methylcyclohexane with alcoholic KOH.<\/strong><\/li>\n<\/ol>\n<p><strong>Ans.<\/strong><\/p>\n<ol start=\"1\">\n<li>(i) \/<img decoding=\"async\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images07.png\" alt=\"\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images07.png\" \/><\/li>\n<li><img decoding=\"async\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images08.png\" alt=\"\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images08.png\" \/><\/li>\n<li><img decoding=\"async\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images09.png\" alt=\"\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images09.png\" \/><\/li>\n<\/ol>\n<\/li>\n<li><strong>(A), (B) and (C) are three non-cyclic functional isomers of a carbonyl compound with molecular formula C<sub>4<\/sub>H<sub>8<\/sub>O. Isomers (A) and (C) give positive Tollens\u2019 test whereas isomer (B) does not give Tollens\u2019 test but gives positive Iodoform test. Isomers (A) and (B) on reduction with Zn(Hg)\/conc. HCl give the same product (D).<\/strong>\n<ol start=\"1\">\n<li><strong>Write the structures of (A), (B), (C) and (D).<\/strong><\/li>\n<li><strong>Out of (A), (B) and (C) isomers, which one is least reactive towards addition of HCN?<br \/>\nAns.<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n<ol start=\"1\">\n<li>A= CH<sub>3<\/sub>CH<sub>2<\/sub>CH<sub>2<\/sub>CHO<br \/>\nB = CH<sub>3<\/sub>COCH<sub>2<\/sub>CH<sub>3<\/sub><br \/>\nC= (CH<sub>3<\/sub>)<sub>2<\/sub>CHCHO<br \/>\nD= CH<sub>3<\/sub>CH<sub>2<\/sub>CH<sub>2<\/sub>CH<sub>3<\/sub><\/li>\n<li>B<\/li>\n<\/ol>\n<ul>\n<li><strong>Write the structures of the main products in the following reactions :<\/strong>\n<ol start=\"1\">\n<li><img decoding=\"async\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images03.png\" alt=\"\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images03.png\" \/><\/li>\n<li><img decoding=\"async\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images04.png\" alt=\"\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images04.png\" \/><\/li>\n<li><img decoding=\"async\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images05.png\" alt=\"\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images05.png\" \/><\/li>\n<\/ol>\n<p><strong>Ans.<\/strong><\/p>\n<ol start=\"1\">\n<li><img decoding=\"async\" src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images10.png\" alt=\"\" data-cke-saved-src=\"https:\/\/media-mycbseguide.s3-ap-south-1.amazonaws.com\/images\/cbse\/12\/Chemistry\/lyp\/2018\/images10.png\" \/><\/li>\n<li>C<sub>6<\/sub>H<sub>5<\/sub>CH(OH)CH<sub>3<\/sub><\/li>\n<li>C<sub>2<\/sub>H<sub>5<\/sub>I + C<sub>6<\/sub>H<sub>5<\/sub>OH (No splitting of marks)<\/li>\n<\/ol>\n<\/li>\n<li>\n<ol start=\"1\">\n<li><strong>Why is bithional added to soap ?<\/strong><\/li>\n<li><strong>What is tincture of iodine? Write its one use.<\/strong><\/li>\n<li><strong>Among the following, which one acts as a food preservative ?<br \/>\nAspartame, Aspirin, Sodium Benzoate, Paracetamol<\/strong><\/li>\n<\/ol>\n<p><strong>Ans.<\/strong><\/p>\n<ol start=\"1\">\n<li>To impart antiseptic properties<\/li>\n<li>2-3% solution of iodine in alcohol \u2013 water mixture \/ iodine dissolved in alcohol, used as an antiseptic\/ applied on wounds.<\/li>\n<li>Sodium benzoate \/ Aspartame<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n<p style=\"text-align: center;\"><strong>These are first 20 questions only.\u00a0<\/strong><b>To view and download complete question paper with solution<\/b><\/p>\n<p style=\"text-align: center;\"><b><strong><a class=\"button\" href=\"https:\/\/play.google.com\/store\/apps\/details?id=in.techchefs.MyCBSEGuide&amp;referrer=utm_source%3Dmycbse_bottom%26utm_medium%3Dtext%26utm_campaign%3Dmycbseads\">Download myCBSEguide App<\/a><\/strong><\/b><\/p>\n<p style=\"text-align: center;\"><b>the best CBSE App from google playstore\u00a0now or login to our Student Dashboard.<\/b><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Chemistry_Question_Paper_2018_with_solution\"><\/span>Chemistry Question Paper 2018 with solution<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Download class 12 Chemistry question paper with solution from best CBSE App the myCBSEguide. CBSE class 12 Chemistry question paper 2018 in PDF format with solution will help you to understand the latest question paper pattern and marking scheme of the CBSE board examination. You will get to know the difficulty level of the question paper. CBSE question papers 2018 for class 12 Chemistry have 26 questions with solution.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Previous_Year_Question_Paper_for_class_12\"><\/span>Previous Year Question Paper for class 12<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>CBSE question papers 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011, 2010, 209, 2008, 2007, 2006, 2005 and so on for all the subjects are available under this download link. Practicing real question paper certainly helps students to get confidence and improve performance in weak areas.<\/p>\n<ul>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-physics\/1251\/cbse-last-year-papers\/3\/\">Physics<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-chemistry\/1267\/cbse-last-year-papers\/3\/\"> Chemistry<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-mathematics\/1284\/cbse-last-year-papers\/3\/\">Mathematics<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-biology\/1298\/cbse-last-year-papers\/3\/\">Biology<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-accountancy\/1315\/cbse-last-year-papers\/3\/\">Accountancy<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-business-studies\/1727\/cbse-last-year-papers\/3\/\">Business Studies<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-economics\/1327\/cbse-last-year-papers\/3\/\">Economics<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-history\/1869\/cbse-last-year-papers\/3\/\">History<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-geography\/1863\/cbse-last-year-papers\/3\/\">Geography<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-political-science\/1879\/cbse-last-year-papers\/3\/\">Political Science<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-physical-education\/1877\/cbse-last-year-papers\/3\/\">Physical Education<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-computer-science\/1851\/cbse-last-year-papers\/3\/\">Computer Science<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-informatics-practices\/1873\/cbse-last-year-papers\/3\/\">Informatics Practices<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-english-core\/1855\/cbse-last-year-papers\/3\/\">English Core<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-hindi-core\/1865\/cbse-last-year-papers\/3\/\">Hindi Core<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12-hindi-elective\/1867\/cbse-last-year-papers\/3\/\">Hindi Elective<\/a><\/li>\n<li><a href=\"http:\/\/mycbseguide.com\/downloads\/cbse-class-12\/1250\/\">Other Subjects<\/a><\/li>\n<\/ul>\n<p>To download CBSE Question Paper 2018 class 12 Accountancy, Chemistry, Physics, History, Political Science, Economics, Geography, Computer Science, Home Science, Accountancy, Business Studies and Home Science; do check myCBSEguide app or website. myCBSEguide provides sample papers with solution, test papers for chapter-wise practice, NCERT solutions, NCERT Exemplar solutions, quick revision notes for ready reference, CBSE guess papers and CBSE important question papers. Sample Paper all are made available through\u00a0<a href=\"https:\/\/play.google.com\/store\/apps\/details?id=in.techchefs.MyCBSEGuide&amp;referrer=utm_source%3Dmycbse_bottom%26utm_medium%3Dtext%26utm_campaign%3Dmycbseads\"><strong>the best app for CBSE students<\/strong><\/a>\u00a0and myCBSEguide website.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Previous Year Question Papers -Download Free PDF CBSE Question Paper 2018 class 12 Chemistry\u00a0conducted by Central Board of Secondary Education, New Delhi in the month of March 2018. CBSE previous year question papers with solution are available in myCBSEguide mobile app and cbse guide website. The Best CBSE App for students and teachers is myCBSEguide &#8230; <a title=\"CBSE Question Paper 2018 class 12 Chemistry\" class=\"read-more\" href=\"https:\/\/mycbseguide.com\/blog\/cbse-question-paper-2018-class-12-chemistry\/\" aria-label=\"More on CBSE Question Paper 2018 class 12 Chemistry\">Read more<\/a><\/p>\n","protected":false},"author":2,"featured_media":-1,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1346,1014,1434],"tags":[1679,1528,320,1342,1711],"class_list":["post-17649","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cbse","category-cbse-question-papers","category-chemistry-cbse-class-12","tag-cbse-last-year-question-paper","tag-cbse-question-paper-2018","tag-chemistry","tag-class-12","tag-previous-year-question-paper"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.0 - 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