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Need mark weightage for every chapters

Posted by Kaviya Kaviya 7 years, 1 month ago

1 answers

Sahana Sankaranarayanan 7 years, 1 month ago

Solid States = 4 marks Solutions= 5 marks Electrochemistry= 5 marks Chemical Kinetics= 5 marks Surface Chemistry=4 marks General Principles and Process of Isolation of Elements= 3 marks P Block Elements=7 marks D BLock Elements=5 marks Coordination Compounds=4 marks Haloalkenes and Haloarenes=3 marks Alcohols, Phenols and Ethers=5 marks Aldehydes, Ketones and Carboxylic Acids=6 marks Organic Compounds=4 marks Biomolecules=3 marks Polymers=3 marks Chemistry in Everyday Life=4 marks Total Marks=70 marks

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Concn. Sulphuric acid has density of 1.95g/cm3 & is 98% by weight. Calculatr the molarity and molality of the solution.

Posted by Nitish Kr. 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Yuvraj Patel 7 years, 1 month ago

Given Density=1.95g/cm3 Weight of H2SO4 =98%=98g Weight of solution =100g Hence, volume of solution =100/1.95 =51.2cm3 Weight of solvent =100-98=2g Molar mass of H2SO4 98g Hence, no. of moles of H2SO4 =Given mass/Molar mass=98/98=1mol Molality =no.of moles *1000/mass of solvent =1*1000/2=500Mol Molarity =no. of moles*1000/volume of solution =1*1000/51.2=19.5Mol

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Why m-aminophenol is a stronger acid than o-aminophenol??

Posted by Nishtha Ag 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Priyanshi Cha 7 years, 1 month ago

Because amino is a ERG .At ortho position it destabilised the phenol by intensify the negative charge while at meta position it remains unaffected.

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How to learn the name rxn??

Posted by Kuldeep Singh 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Tanya Majumdar 7 years, 1 month ago

Just remember the process how they react and also the type compounds they rect with

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How to manage time in chemistry exam ???......means how much time must be devoted to each section..

Posted by Amanpreet Aulakh 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Tanya Majumdar 7 years, 1 month ago

1 in very short,2 to 5 in shorts,6 to 8 in sec c, 9 to 11 min in longs.

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Define first order reaction

Posted by Ayushi Vastrakar 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Prit Gajera 7 years, 1 month ago

In rate law expression if sum of the power of reactants is one then it is known as first order reaction

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Simplest way to calculate acidity or basicity of a compound?

Posted by Himanshu Thakur 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Sanskriti S 7 years, 1 month ago

if u know the structure of compound, then u can easily determine acidity/basicity as it is the no. of ionisable OH-/H+ ions. there isn't any other way.. I think..

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Wrought iron is the purest form of iron write a reaction used for the preparation of wrought iron from cast iron . How can the impurities of sulphur , silicon and phosphorus be removed from cast iron

Posted by Anjali Chaurasia 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Sanskriti S 7 years, 1 month ago

Fe2O3 + 3C -----> 2Fe + 3CO ; S, Si & P react with O2 to form slag. Si + O2 ----> SiO2(slag) S + O2 ----> SO2 2P + 5O2 -----> P2O5

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All important name reaction...??

Posted by Shivangi Singh 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Prit Gajera 7 years, 1 month ago

[email protected]

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formula of bi-phenyl

Posted by A B 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Ts Parmar 7 years, 1 month ago

C12H10

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what is 2CH3CHO

Posted by A B 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Amanpreet Aulakh 7 years, 1 month ago

Acetaldehyde...green apple smell.....found in ripe fruits

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wha is 2CH3CHO

Posted by A B 7 years, 1 month ago

CBSE > Class 12 > Chemistry

0 answers

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Examples of vacancy and interstitial defects.

Posted by Himanshu Thakur 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Sanskriti S 7 years, 1 month ago

NaCl, KCl, CsCl, etc. exhibit vacancy defect Hydrogen, palladium etc. show interstitial defect

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Why Aspartame is limited to the food and soft drinks in cold condition

Posted by Sneha Bhosale 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Rohit Jain 7 years, 1 month ago

Because Aspartame becomes unstable at high (cooking) temperature

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How to prepare chemistry in 5 days

Posted by Saksham Sharma 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Anshika Pahariya 7 years, 1 month ago

Divide the whole syllabus in three parts- Physical Inorganic Organic Prepare organic in the last days, so that you don't forget it during exam Read all the examples within in the chapters thoroughly Prepare all the intext ques Get ready for 60/70 marks!

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The bond lenght of c-cl bond is larger in haloalkanes than that in haloarenes

Posted by Vish Raj 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Kartik Periwal 7 years, 1 month ago

Because in haloarenes c-cl bond gets double character and hence bond length of decrease

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What is step growth polymerisation?Explain the steps involved in this process.

Posted by Suyash Tripathi 7 years, 1 month ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

What is redox reaction?

Posted by Jogender Yadav 7 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Amrit Kaur 7 years, 1 month ago

Oxidation and reductipn reactions

2Thank You

Jogender Yadav 7 years, 1 month ago

Simultaneously both oxidation and reduton take place.

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16 group element

Posted by Anurag Yadav 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Sonu Sharma 7 years, 1 month ago

Oxygen family

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Why fluorine can not give haloform reaction??

Posted by Suhani Rana? 7 years, 1 month ago

CBSE > Class 12 > Chemistry

3 answers

Sanskriti S 7 years, 1 month ago

if haloform reacn. is carried out for fluorine, then energy released when new bond (C-F) is formed is much greater than that required to break C-C bond due to its small size & high electronegativity. So the reacn. is explosive in nature.

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Suhani Rana? 7 years, 1 month ago

Can you please elaborate it..

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Sonu Sharma 7 years, 1 month ago

Due to small in size

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How to calculate vant hoff's factor for a given compound of certain molarity?

Posted by Himanshu Thakur 7 years, 1 month ago

CBSE > Class 12 > Chemistry

0 answers

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Define narrow spectrum antibotics

Posted by Amrit Kaur 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Suyash Tripathi 7 years, 1 month ago

Those antibiotic which are effective against the particular type of bacteria . Ex- penicillin G

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what is the coordination no. Of ca and f2 in caf2

Posted by Rakesh Tiwari 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Sanskriti S 7 years, 1 month ago

Ca - 8 d F2 - 4

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Example of antifertility drugs

Posted by Rishabh Shukls 7 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Mandeep Sandhu 7 years, 1 month ago

Norethindrone and novestrol

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Amrit Kaur 7 years, 1 month ago

Mifepristone, ormeloxifene

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Explain reactivity toward oxygen in grp 15 element

Posted by Aayush Gupta 7 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Amrit Kaur 7 years, 1 month ago

The elements os group number 15 form two types of oxides E2O3 and E2O5. The oxide in the higher o.s is more acidic than that of lower o.s. Their acidic character decreases down the group. E2O5 type oxides of N and P are purely acidic while oxides of As and Sb are amphoteric and oxides of Bi are basic.

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What is the normality of - 1.5M H2SO4

Posted by Himanshu Thakur 7 years, 1 month ago

CBSE > Class 12 > Chemistry