The opening chapters of NCERT Class 11 Chemistry supply several easy marks in NEET every year. This set covers the mole concept, molarity and molality, empirical formula, limiting reagent, quantum numbers, periodic trends, hybridisation, VSEPR shapes and molecular orbital bond order.
How to practise: read each question and tap the option you think is correct. You will see right away whether you got it, along with a short explanation, and your score is tracked at the bottom of the screen. This set has 15 questions.
Topics covered in this set
- Moles, molecules and molar volume
- Molarity, molality and limiting reagent
- Empirical formula
- Quantum numbers and nodes
- Periodic trends
- Hybridisation, VSEPR and bond order
NEET Chemistry MCQs with answers and explanations
Q1. How many water molecules are present in 9 g of water? (N_A = 6.022 × 10²³ mol⁻¹)
a) 3.011 × 10²³
b) 6.022 × 10²³
c) 1.5 × 10²³
d) 1.204 × 10²⁴
Q2. What volume does 8 g of oxygen gas occupy at STP? (Take molar volume = 22.4 L mol⁻¹)
a) 22.4 L
b) 2.8 L
c) 11.2 L
d) 5.6 L
Q3. 4 g of NaOH is dissolved in water to make 250 mL of solution. What is the molarity?
a) 0.04 M
b) 0.4 M
c) 0.1 M
d) 1.6 M
Q4. 18 g of glucose (C₆H₁₂O₆) is dissolved in 500 g of water. What is the molality of the solution?
a) 0.36 m
b) 0.02 m
c) 0.2 m
d) 0.1 m
Q5. A compound contains 40% carbon, 6.67% hydrogen and 53.33% oxygen by mass. What is its empirical formula?
a) C₂H₄O
b) CH₃O
c) CHO
d) CH₂O
Q6. 4 g of H₂ reacts with 16 g of O₂ to form water (2H₂ + O₂ → 2H₂O). What mass of water is formed?
a) 18 g
b) 20 g
c) 9 g
d) 36 g
Q7. Which set of quantum numbers (n, l, mₗ, mₛ) is NOT allowed for an electron?
a) 2, 1, 0, −½
b) 2, 2, 1, +½
c) 4, 0, 0, −½
d) 3, 2, −2, +½
Q8. How many radial nodes and angular nodes does a 4d orbital have?
a) 0 radial and 3 angular
b) 1 radial and 2 angular
c) 3 radial and 0 angular
d) 2 radial and 1 angular
Q9. Which order of orbital energies in a multi-electron atom follows the (n + l) rule?
a) 3d < 4s < 4p < 5s
b) 4s < 4p < 3d < 5s
c) 4s < 3d < 5s < 4p
d) 4s < 3d < 4p < 5s
Q10. Which order of first ionisation enthalpy is correct?
a) C < B < N < O
b) O < N < C < B
c) B < C < N < O
d) B < C < O < N
Q11. What is the correct order of ionic radii for the isoelectronic ions O²⁻, F⁻, Na⁺ and Mg²⁺?
a) F⁻ > O²⁻ > Mg²⁺ > Na⁺
b) Na⁺ > Mg²⁺ > O²⁻ > F⁻
c) O²⁻ > F⁻ > Na⁺ > Mg²⁺
d) Mg²⁺ > Na⁺ > F⁻ > O²⁻
Q12. Which element has the most negative electron gain enthalpy?
a) Fluorine
b) Bromine
c) Chlorine
d) Oxygen
Q13. What is the shape of the ClF₃ molecule according to VSEPR theory?
a) See-saw
b) Trigonal planar
c) Trigonal pyramidal
d) T-shaped
Q14. Which species has the highest bond order and therefore the shortest O–O bond?
a) O₂²⁻
b) O₂⁺
c) O₂
d) O₂⁻
Q15. How many σ and π bonds are present in acrylonitrile, CH₂=CH–C≡N?
a) 5 σ and 3 π
b) 6 σ and 3 π
c) 6 σ and 2 π
d) 7 σ and 2 π
Quick revision notes
- Moles = mass/molar mass = particles/N_A = volume at STP/22.4 L.
- Molarity = mol per litre of solution; molality = mol per kg of solvent.
- Nodes: radial = n − l − 1, angular = l, total = n − 1.
- IE anomalies: Be > B and N > O; Cl has the most negative electron gain enthalpy.
- Bond order = (Nb − Na)/2: O₂⁺ 2.5, O₂ 2, O₂⁻ 1.5, O₂²⁻ 1.
Frequently asked questions
Are these NEET previous year questions?
No. They are original practice questions based on the NCERT Class 11 chapters Some Basic Concepts of Chemistry, Structure of Atom, Classification of Elements and Chemical Bonding.
Should I use 22.4 L or 22.7 L for molar volume?
NCERT gives 22.7 L at 1 bar and 273 K, while many questions use 22.4 L at 1 atm. Use the value the question states, and check which one matches the options.
How do I find hybridisation quickly?
Count the bond pairs and lone pairs around the central atom: 2 means sp, 3 sp², 4 sp³, 5 sp³d and 6 sp³d².
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