Top Solid State Questions for NEET
Solid State is a highly scoring chapter in NEET Chemistry, known for its predictable question patterns and direct NCERT-based concepts. Questions are frequently asked from crystal structures, packing efficiency, defects, and electrical properties. Practicing the Top 5 Solid State Questions ensures strong conceptual clarity and helps you tackle both numerical and theory-based problems with confidence.
Why Solid State is Important for NEET
The Solid State chapter consistently contributes 1–2 questions in NEET. Most questions are formula-based or conceptual, making it a high-return topic. By mastering the Top 5 Solid State Questions, you can secure easy marks with minimal effort compared to more complex chapters.
Top 5 Solid State Questions (Most Expected PYQs)
Question 1: Packing Efficiency in FCC
What is the packing efficiency of a face-centered cubic (FCC) unit cell?
A. 52%
B. 68%
C. 74%
D. 76%
Answer: C
Explanation:
FCC structures have the highest packing efficiency of 74%. This arises due to close packing of atoms. Among the Top 5 Solid State Questions, this is one of the most frequently repeated numericals.
Question 2: Number of Atoms in Unit Cell
How many atoms are present in a body-centered cubic (BCC) unit cell?
A. 1
B. 2
C. 4
D. 6
Answer: B
Explanation:
In BCC, one atom is present at the center and 8 corner atoms contribute 1 atom in total (1/8 × 8). Thus, total atoms = 2. This concept is essential when solving Top 5 Solid State Questions.
Question 3: Coordination Number
What is the coordination number of a simple cubic lattice?
A. 4
B. 6
C. 8
D. 12
Answer: B
Explanation:
Each atom in a simple cubic structure is surrounded by 6 nearest neighbors. Coordination number is a fundamental concept tested in Top 5 Solid State Questions.
Question 4: Density of Unit Cell
The density of a unit cell is given by:ρ=a3⋅NAZ⋅M
Which factor increases density?
A. Increase in edge length
B. Decrease in molar mass
C. Increase in number of atoms per unit cell
D. Decrease in Avogadro number
Answer: C
Explanation:
Density increases with more atoms in the unit cell (Z). This formula is one of the most important in Top 5 Solid State Questions and is frequently used in numericals.
Question 5: Schottky Defect
Which statement is correct for Schottky defect?
A. Density increases
B. Equal number of cations and anions missing
C. Only cations missing
D. Occurs in covalent solids
Answer: B
Explanation:
Schottky defect involves equal missing cations and anions, maintaining electrical neutrality but decreasing density. This is a classic NCERT-based concept in Top 5 Solid State Questions.
Key Concepts You Must Remember
While preparing the Top 5 Solid State Questions, you must focus on unit cell types (SC, BCC, FCC), coordination number, packing efficiency, and density formula. Defects like Schottky and Frenkel are frequently tested, along with electrical properties of solids (conductors, semiconductors, insulators).
Additional Practice Questions (Concept-Based Rapid Revision)
Question 6
What is the packing efficiency of BCC?
Answer: 68%
Question 7
Which solid has the highest coordination number?
Answer: FCC (12)
Question 8
Which defect does not change density?
Answer: Frenkel defect
Question 9
Which type of solid conducts electricity?
Answer: Metallic solid
Question 10
Which lattice has atoms only at corners?
Answer: Simple cubic lattice
Additional Practice Questions with Solutions
Question 11
Why does Schottky defect decrease density?
Solution:
Atoms are missing from lattice points, reducing mass while volume remains constant.
Question 12
Why is FCC more stable than BCC?
Solution:
FCC has higher packing efficiency, leading to greater stability.
Question 13
Why are metals good conductors?
Solution:
Presence of free electrons allows easy flow of electricity.
Question 14
Why is diamond a poor conductor?
Solution:
No free electrons; all electrons are involved in covalent bonding.
Question 15
Why does increasing edge length decrease density?
Solution:
Density is inversely proportional to volume (a³). Larger edge length increases volume, reducing density.
Final Revision Tips
To master the Top 5 Solid State Questions, revise formulas regularly and practice numericals daily. Focus on NCERT tables and examples, especially crystal structures and defects. Keep revisiting the Top 5 Solid State Questions to ensure speed and accuracy during the exam.
Consistent practice of the Top 5 Solid State Questions will help you confidently solve both direct and tricky NEET problems.