Chapter 1: Solid State

NCERT Solutions for CBSE Class 10 Chemistry — 18 solved questions with detailed explanations.

Questions

Topics

Solved Questions

Q1. The coordination number of each atom in BCC structure is:

Difficulty: Easy-Medium · Topic: Crystal Structure

Solution

In BCC, each atom is surrounded by 8 nearest neighbors (body center touches 8 corners).

Q2. The packing efficiency of FCC structure is approximately:

Difficulty: Easy-Medium · Topic: Packing

Solution

FCC packing efficiency = 74% (close-packed arrangement). BCC = 68%, Simple cubic = 52%.

Q3. Schottky defect decreases the density because:

Atoms are displaced
Equal number of cations and anions are missing
Only cations are missing
Extra atoms are present

Difficulty: Easy-Medium · Topic: Crystal Defects

Solution

Schottky defect: equal number of cations and anions leave their lattice sites, creating vacancies and decreasing density.

Q4. FCC unit cell contains:

1 atom
6 atoms
2 atoms
4 atoms

Difficulty: Easy-Medium · Topic: Solid State

Solution

4 atoms.

Q5. BCC unit cell contains:

1 atom
4 atoms
6 atoms
2 atoms

Difficulty: Easy-Medium · Topic: Solid State

Solution

2 atoms.

Q6. Simple cubic unit cell contains:

6 atoms
1 atom
2 atoms
4 atoms

Difficulty: Easy-Medium · Topic: Solid State

Solution

1 atom.

Q7. HCP has coordination number:

Difficulty: Easy-Medium · Topic: Solid State

Solution

12.

Q8. Frenkel defect occurs when:

ion moves to interstitial site
no defect
ions leave lattice
extra ions added

Difficulty: Easy-Medium · Topic: Solid State

Solution

ion moves to interstitial site.

Q9. Band gap in conductors is:

infinite
zero or very small
large (> 3 eV)
moderate (1-3 eV)

Difficulty: Easy-Medium · Topic: Solid State

Solution

zero or very small.

Q10. Band gap in insulators is:

moderate
large (> 3 eV)
small (< 1 eV)
zero

Difficulty: Easy-Medium · Topic: Solid State