CBSE > Class 12 > Chemistry | CBSE Board | Homework Help

Number of atoms in close packaging = 0.5 mol 1 has 6.022 ×10 23 particles So that, Number of close−packed particles = 0.5 × 6.022 × 1023 = 3.011 × 1023 Number of tetrahedral voids = 2 × number of atoms in close packaging Plug the values we get, Number of tetrahedral voids = 2 × 3.011 × 1023 = 6.022 × 1023 Number of octahedral voids = number of atoms in close packaging So that, Number of octahedral voids = 3.011 × 1023 Total number of voids = Tetrahedral void + octahedral void = 6.022 × 1023 + 3.011 × 1023 = 9.03 × 1023

3Thank You

ANSWER

While filling up of electrons in the atomic orbitals the 4s orbital is filled before the 3d orbital.........explain with reference to d- and f-block elements

Posted by Nancy Yadav 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

In first transition 3d series cu has exceptionally positive E°M2+/M value.why?

Posted by Nancy Yadav 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Phenol associated in benzene and form a dimer (c6H5oH )2 the freezing point of Sol containing 5 g of phenol into 250 g of c6h6 is lowered by .10 c calculate the degree of associated I n phenol

Posted by Aman Sisodia 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

what is CMC

Posted by Smriti Pandey 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Nisha Beniwal 8 years, 3 months ago

Critical micellisation conc. Means micelles formation take place above the particular conc.

0Thank You

ANSWER

why do ether used to prepare the grignard reagent as solvent from alkyl halide and magnesium

Posted by Smriti Pandey 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Shorten the answer plz?

Posted by Skrillex Levine 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Structure of (HPO3)3

Posted by Saurav Tanwar 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Shruti R 8 years, 3 months ago

O II P=OH /. | O. O /. | / HO =P. __ O _ P=OH II. II O O O.

0Thank You

ANSWER

Why hypercojucation is permanent effect and mesomeric effectis temporary effect?

Posted by Vivek Tiwari 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Define micelles formation???? Plzz comment

Posted by Nisha Beniwal 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Define mass percentage

Posted by Sachin Saini 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Kritika Trehan 8 years, 3 months ago

Mass percentage is one way of representing the concentration of an element in a compound or a component in a mixture. Mass percentage is calculated as the mass of a component divided by the total mass of the mixture, multiplied by 100%.

Also Known As: mass percent, (w/w)%

1Thank You

ANSWER

Role of zn in extraction of silver

Posted by Mohin Nadaf 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

How can I improve my organic chemistry....specially conversions??

Posted by Apoorve Singh 8 years, 3 months ago

CBSE > Class 12 > Chemistry

3 answers

Nisha Beniwal 8 years, 3 months ago

Women men se jadha perfect hoti h ?????

1Thank You

Vineit Kumar Gupta 8 years, 3 months ago

Practice makes a man perfect well i cant say about women's ???

0Thank You

Nikhil Maurya 8 years, 3 months ago

Yes you can, by practising it...

7Thank You

ANSWER

Explain Nernest equation

Posted by Aakash Biswas 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Method of preparation of carboylic acid from alkyl benzenes description

Posted by Sahiba Samant 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

(CH3)3C-CHO doesnot undergo aldol condensation .comment.

Posted by Ashish Bhatia 8 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Summi Farheen 8 years, 3 months ago

Absence of alpha Hydrogen

1Thank You

Nisha Beniwal 8 years, 3 months ago

Bcoz no OH present

2Thank You

ANSWER

Interstates means

Posted by Vikram Roy 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Difference between molarity and molality

Posted by Tarash Baskey 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 4 years, 9 months ago

The molality of a solution is equal to the moles of solute divided by the mass of solvent in kilograms, while the molarity of a solution is equal to the moles of solute divided by the volume of solution in liters.

0Thank You

ANSWER

Why cr+2 act as reducing agent but Mn +2 act as oxidising agent though both have same electeonic configuration

Posted by Virendra Aditya 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

what is the sucrose needs to dissolved 1000g of water in order to decrease the vapour pressure by 30%?

Posted by Pratyush Srivastava 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Why Mn+2 compounds are more stable than Fe+2 towards oxidation to their +3 state?

Posted by Chandeliya Rock 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Rashi Bari 8 years, 3 months ago

Due to the the presence of half filled d orbital

4Thank You

ANSWER

Name a ore having two metal atoms.

Posted by Naveen Garg 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Ritu Sharma 8 years, 3 months ago

Sulphide ores

0Thank You

ANSWER

What happens when H3PO3 is heated?

Posted by Madhavi Likhar 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Vaishnavi Kumari 8 years, 3 months ago

When H3PO3 is heated it gives the reaction Please put the heat sign above the arrow mark H3PO3----------> H3PO4 +PH3

4Thank You

ANSWER

Explain brown ring test??

Posted by Nisha Beniwal 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Naveen Sharma 8 years, 3 months ago

A common nitrate test, known as the brown ring test can be performed by adding iron(II) sulfate to a solution of a nitrate, then slowly adding concentrated sulfuric acid such that the acid forms a layer below the aqueous solution. A brown ring will form at the junction of the two layers, indicating the presence of the nitrate ion.

The overall reaction is the reduction of the nitrate ion by iron(II) which is oxidised to iron(III) and formation of a nitrosonium complex where nitric oxide is reduced to NO⁻.

{tex}2HNO_3+ 3H_2SO_4 + 6FeSO_4 \to 3Fe_2(SO_4)_3 + 2NO + 4H_2O{/tex}
{tex}[Fe(H_2O)_6]SO_4 + NO = [Fe(H_2O)_5(NO)]SO_4+ H_2O{/tex}

2Thank You

ANSWER

Why does carboxylic acid doesn't give reaction with carbonyl compounds?

Posted by Sukarn Pahuja 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Naveen Sharma 8 years, 3 months ago

The carbonyl carbon in ketones and aldehydes is more electrophilic than in carboxylic acids.This is because the lone pairs on oxygen atom attached to hydrogen atom in the -COOH group are involved in resonance thereby making the carbon atom less electrophilic.

Hence, carboxylic acids do not give characteristic reaction of carbonyl group.

2Thank You

ANSWER

Very important 10structure in organic chemistry

Posted by Suyash Dwivedi 8 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Which is More coagulated positive charged NaCl or BaSO4

Posted by Shalik Dubey 8 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Nancy Yadav 8 years, 3 months ago

Baso4 bcoz it has more neg chrg

1Thank You

ANSWER

Why zinc oxide which is white in color does become yellow heating?

Posted by Priyanka Choudhary 8 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Virendra Aditya 8 years, 3 months ago

ZnO turns yellow on heating due to non stoichiometric defact i.e. metal excess defact. This defact is caused by extra cations in the interstitial site . On heating oxygen escapes the lattice leaving behind the electron which give ZnO YELLOW COLOUR

1Thank You

Nisha Beniwal 8 years, 3 months ago

Due to the presence of f-centre

0Thank You

ANSWER