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what is syn gas and how it is prepared nowdays

Posted by SHIVAM JAISWAL (Mar 20, 2017 1:07 a.m.) (Question ID: 4160)

Oxidation number of N in (NH4)2 SO4

 

Posted by fazil khan (Mar 19, 2017 12:40 p.m.) (Question ID: 4108)

What is green chemistry

Posted by Khizer Ansari (Mar 17, 2017 9:11 p.m.) (Question ID: 4028)

  • Answers:
  • Ans. Green chemistry, also called sustainable chemistry, is an area of chemistry and chemical engineering focused on the designing of products and processes that minimize the use and generation of hazardous substances.

    Answered by Naveen Sharma (Mar 17, 2017 10 p.m.)
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derive the equation Kp=Kc(RT)

Posted by jay patel (Mar 17, 2017 9:20 a.m.) (Question ID: 3967)

discuss the diagonal relationship between Be and Al

Posted by jay patel (Mar 17, 2017 9:18 a.m.) (Question ID: 3966)

  • Answers:
  • Ans. The ionic radius of Be2+ is estimated to be 31 pm : the charge/ radius ratio is nearly the same as that of the Al3+ ion. Hence beryllium resembles aluminium in some ways. Some of the similarities are:

    • Like aluminum, beryllium is not readily attacked by acids because of the presence of an oxide film on the surface of the metal.
    • Beryllium hydroxide dissolves in excess of alkali to give a beryllate ion, just as aluminium hydroxide gives aluminate ion.
    • The chlorides of both beryllium and aluminium have Cl- bridged chloride structure in vapour phase. Both the chlorides are soluble in organic solvents and are strong Lewis acids. They are used as Friedel Craft catalysts.
    • Beryllium and aluminium ions have strong tendency to form complexes.
    Answered by Naveen Sharma (Mar 17, 2017 9:46 a.m.)
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compare the structure of water molecule and ice?

Posted by jay patel (Mar 17, 2017 9:16 a.m.) (Question ID: 3965)

Limiting reagent 

Posted by anish babu (Mar 15, 2017 7:38 p.m.) (Question ID: 3858)

  • Answers:
  • The limiting reagent (or limiting reactant) in a chemical reaction is the substance that is totally consumed when the chemical reaction is complete. The amount of product formed is limited by this reagent, since the reaction cannot continue without it.

    Answered by Shweta Gulati (Mar 15, 2017 7:52 p.m.)
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calculate volume of 4.4 g of CO2 at stp

Posted by Pooja Verma (Mar 10, 2017 12:38 p.m.) (Question ID: 3418)

  • Answers:
  • Ans. No. of moles of CO2 present=given mass /molar mass

    => 4.4/44 = 0.1 moles

    No. of moles = given vol. / 22.4 litres

    => 0.1= given vol./22.4 litres

    => 0.1*22.4 = given vol.

    Given vol is the required vol. here,

    So the vol. occupied by 4.4g of CO2 is 2.24 litres.

    Answered by Naveen Sharma (Mar 10, 2017 5:20 p.m.)
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the 1st ionization energy of nitrogen is greater than oxygen but the 2nd  ionization energy of oxygen is greater than nitrogen. why?

Posted by Pooja Verma (Mar 10, 2017 12:28 p.m.) (Question ID: 3415)

  • Answers:
  • Due  to extra stability of half filled orbital.

    Answered by Supriya Kumari (Mar 10, 2017 1:06 p.m.)
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Explain the principle of paper chromatography?

Posted by Navneet chauhan (Mar 09, 2017 10:09 a.m.) (Question ID: 3352)

  • Answers:
  • Ans. Principle of paper chromatography: The principle involved is partition chromatography wherein the substances are distributed or partitioned between liquid phases. One phase is the water, which is held in the pores of the filter paper used; and other is the mobile phase which moves over the paper. The compounds in the mixture get separated due to differences in their affinity towards water (in stationary phase) and mobile phase solvents during the movement of mobile phase under the capillary action of pores in the paper.

    The principle can also be adsorption chromatography between solid and liquid phases, wherein the stationary phase is the solid surface of paper and the liquid phase is of mobile phase.

    But most of the applications of paper chromatography work on the principle of partition chromatography, i.e. partitioned between to liquid phases.

    Answered by Naveen Sharma (Mar 09, 2017 11:21 a.m.)
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Define entropy and show entropy is a state function

 

Posted by Suhail Ali (Mar 08, 2017 12:57 p.m.) (Question ID: 3292)

Define entropy

 

Posted by Suhail Ali (Mar 08, 2017 12:56 p.m.) (Question ID: 3291)

  • Answers:
  • Ans. Entropy is a thermodynamic state quantity which is a measure of randomness or disorder of the molecules of the system.

    Answered by Naveen Sharma (Mar 08, 2017 4:49 p.m.)
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Balance the equation by basic  medium by ion electron method 

P4  +  OH->  PH3  +  HPO2-

 

Posted by Komal Kumari (Mar 07, 2017 9:29 a.m.) (Question ID: 3221)

What is redox reactions ? All chemical reactions are redox ,if not why?

Posted by Komal Kumari (Mar 07, 2017 9:24 a.m.) (Question ID: 3219)

Why molecules of larger size can be easily polarized ?

Posted by Ashmita Tokas (Mar 06, 2017 2:13 p.m.) (Question ID: 3170)

  • Answers:
  • Ans. In large ions, the charge is distributed over a large area, because of which the charge per unit volume is less. Therefore the hold of the nucleus on the outermost electrons is less, because of which the electronic distribution in these ions can be easily disturbed (or they can be easily polarised), when a small ion comes closer to these ions.

    Answered by Naveen Sharma (Mar 09, 2017 11:31 a.m.)
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What is scrondinger equation.

Posted by Rajat Khurana (Mar 04, 2017 5:49 p.m.) (Question ID: 3051)

How is that silicon atoms can have a coordination number more than four but carbon atom cannot?

Posted by Mohammad Haroon (Mar 04, 2017 4:37 p.m.) (Question ID: 3046)

why amminoa has higher dipole momentvthan nf3

 

Posted by Pradiksha Bablu (Mar 03, 2017 8:59 a.m.) (Question ID: 2947)

  • Answers:
  • Ans. 

    This is due to the fact that dipole moment is a vector quantity and hence resultant dipole moment in a molecule will depend upon the direction of dipole moments of individual bonds.

    Nitrogen has a lone pair of electrons and is more electronegative than hydrogen. So, in case of NH3, the orbital moment due to the lone pair of electrons on nitrogen is in the same direction of the 3 N-H dipoles.Thus, the molecule has a net dipole moment and it is polar.

    In NF3, fluorine being more electronegative than nitrogen pulls the shared pair of electrons of the N-F bonds towards itself. Because of this, the orbital moment due to lone pair of electrons and the resultant dipole moment of 3 N-F bonds point in the opposite directions to that of lone pair of electrons. This lowers the dipole moment of NF3.

    Answered by Naveen Sharma (Mar 03, 2017 12:03 p.m.)
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Did noble gases have largest size in their own period ?

Posted by Manya Singh (Mar 01, 2017 9:46 p.m.) (Question ID: 2887)

Meaning of neucleophile

Posted by Abhishek Rai (Feb 28, 2017 6:15 a.m.) (Question ID: 2765)

  • Answers:
  • Ans. A Nucleophile is a chemical species that donates an electron pair to an electrophile to form a chemical bond in relation to a reaction. All molecules or ions with a free pair of electrons or at least one pi bond can act as Nucleophiles. Because nucleophiles donate electrons, they are by definition Lewis bases.

    Answered by Naveen Sharma (Feb 28, 2017 11:51 a.m.)
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Arrange in increasing order of non metallic character 

Nitrogen,phosphorus,oxygen,sulphur

Posted by Hemang Shrimali (Feb 27, 2017 8:33 p.m.) (Question ID: 2747)

Which element used in photoelectric cell

Posted by Manish Kumar (Feb 26, 2017 4:45 p.m.) (Question ID: 2692)

  • Answers:
  • Caesium (Cs)  Since it has low ionisation enthalpy.

    Answered by Devanshu Agarwal (Feb 27, 2017 1 p.m.)
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2nd essential condition of keto enol tautomerism the first one is it must contain at least one alpha hydrogen atom .....

Posted by Vivek Kumar (Feb 23, 2017 7:17 a.m.) (Question ID: 2484)

HF is more polar than HCl give reason?

Posted by Ábĥí Śhéķ (Feb 22, 2017 11:12 p.m.) (Question ID: 2482)

  • Answers:
  • Fluorine is more electronegative than chlorine. Hence, HF has more polarity than HCl. 

    Answered by Shweta Gulati (Feb 23, 2017 12:08 a.m.)
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Define molarity solution is prepared by dissolving 18 gram of glucose in 500 ml of water calculate its molarity which will change with temperature and why M and m

Posted by Aditya Gupta (Feb 22, 2017 8:50 p.m.) (Question ID: 2474)

  • Please give me answer

    Posted by Aditya Gupta (Feb 22, 2017 8:56 p.m.)
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  • Answers:
  • <h4>Answer:</h4>

    <a href="http://socratic.org/chemistry/solutions-and-their-behavior/molarity">Molarity</a> is the concentration of a solution expressed as the number of moles of solute per litre of solution.

    <h4>Explanation:</h4>

    To get the molarity, you divide the moles of solute by the litres of solution

     

    Molarity=moles of solute / litres of solution

    Molarity decreases when temperature increases.

    <h4>Explanation:</h4>

    Molarity is affected by temperature because it is based on the volume of the solution, and the volume of a substance will be affected by changes in temperature.

    In general, volume will increase when temperature increases, and vice versa. So if we use an example where temperature is increasing, that means the L in that equation is getting larger as well. Since we are dividing by L, (and dividing by a larger number gives a smaller answer,) M will become smaller.

     

     

    Answered by srinivas chandra (Feb 23, 2017 8:39 p.m.)
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. (i) Give two industrial applications of distillation under reduced pressure. (ii) Why is it necessary to use acetic acid and not hydrochloric acid for acidification of sodium extract for testing sulphur by lead acetate test?

Posted by Slr Teja (Feb 22, 2017 7:25 a.m.) (Question ID: 2427)

  • Answers:
  • Ans. (i)Distillation Under Reduced Pressure is used for purifying or separating thermally unstable liquid compounds.

    Uses :

    • In Petroleum Refining
    • in food processing

    (ii) For testing of sulphur present in the organic compound, the Lassaigne’s extract is acidified with acetic acid (CH3COOH) and not sulphuric acid because lead acetate is soluble and does not interfere with the test. If sulphuric acid (H2SO4 ) is used, lead acetate will react with H2SO4 itself to form white ppt. PbSO4.

    Answered by Naveen Sharma (Feb 22, 2017 12:01 p.m.)
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. Which species is the smallest aromatic substance?

Posted by Lokesh i47 (Feb 21, 2017 9:40 p.m.) (Question ID: 2411)

  • Answers:
  • The cyclopropenyl cation is the smallest aromatic substance.

    As to π electrons, when n = 0, the ordinary cyclopropene molecule is not aromatic. It becomes aromatic only if the third π electron is missing. That is, when it becomes the cyclopropenyl cation and its ring has a positive charge.

    Answered by Shweta Gulati (Feb 21, 2017 10:41 p.m.)
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IUPAC NAME OF CH3COCH2CH2CH2COOH

Posted by nilesh Kumar (Feb 17, 2017 4:33 p.m.) (Question ID: 2245)

  • Answers:
  • Ans. 5-oxohexanoic acid

    Answered by Naveen Sharma (Feb 17, 2017 5:13 p.m.)
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What is buffer solution

 

Posted by alol dubey (Feb 16, 2017 6 a.m.) (Question ID: 2183)

  • Answers:
  • Ans. A buffer solution is one which resists changes in pH when small quantities of an acid or an alkali are added to it.

    A common example would be a mixture of ethanoic acid and sodium ethanoate in solution.

    Answered by Naveen Sharma (Feb 16, 2017 9:52 a.m.)
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explain haeber's process

Posted by Shreya Maity (Feb 15, 2017 7:14 p.m.) (Question ID: 2155)

  • Answers:
  • The process converts atmospheric nitrogen (N2) to ammonia (NH3) by a reaction with hydrogen (H2) using a metal catalyst under high temperatures and pressures:

    <dl> <dd>N2 + 3 H2 → 2 NH3     (Δ<i>H°</i> = −91.8 kJ) => (Δ<i>H°</i> = −45.8 kJ·mol−1)</dd> </dl>
    Answered by Shweta Gulati (Feb 15, 2017 9:33 p.m.)
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