IB DP Chemistry Mock Exam SL Paper 1A Set 4 - 2025 Syllabus

IB DP Chemistry Mock Exam SL Paper 1A Set 4

Prepare for the IB DP Chemistry Exam with our comprehensive IB DP Chemistry Exam Mock Exam SL Paper 1A Set 4. Test your knowledge and understanding of key concepts with challenging questions covering all essential topics. Identify areas for improvement and boost your confidence for the real exam

IB DP Chemistry Mock Tests -All Sets

Question

Which property stays the same for water containing tritium (\(^3H\)) and water containing hydrogen (\(^1H\))?

(A) Density
(B) Dipole moment of a molecule
(C) Boiling point
(D) Relative molecular mass

▶️ Answer/Explanation

Detailed solution

Isotopes have the same electron configuration and thus the same molecular geometry and polarity. The dipole moment depends on the charge separation and molecular shape, which are identical for H₂O and T₂O. Density, boiling point, and relative molecular mass differ due to the different atomic masses.
✅ Answer: (B)

Question

What is the greatest number of electrons that can be accommodated in the main energy level where \( n = 3 \)?

(A) 3
(B) 8
(C) 18
(D) 28

▶️ Answer/Explanation

Detailed solution

The maximum number of electrons in a principal energy level is given by \( 2n^2 \). For \( n = 3 \), this is \( 2 \times (3)^2 = 18 \).
✅ Answer: (C)

Question

Which of the following molecules has a net dipole moment?

(A) \( \text{CH}_4 \)
(B) \( \text{C}_6\text{H}_6 \)
(C) \( \text{SO}_2 \)
(D) \( \text{CO}_2 \)

▶️ Answer/Explanation

Detailed solution

A molecule is polar if it has polar bonds and an asymmetric shape. CH₄ (tetrahedral) and CO₂ (linear) are symmetrical, so their bond dipoles cancel. C₆H₆ (benzene) is a symmetrical planar molecule. SO₂ has a bent geometry, resulting in a net dipole moment.
✅ Answer: (C)

IB DP Chemistry Mock Exam SL Paper 1A Set 4 - 2025 Syllabus