DP Chemistry (first assessment 2025)

Test builder »

Question 21N.1A.SL.TZ0.2

Date	November 2021	Marks available	[Maximum mark: 1]	Reference code	21N.1A.SL.TZ0.2
Level	SL	Paper	1A	Time zone	TZ0
Command term	Solve	Question number	2	Adapted from	N/A

2.

[Maximum mark: 1]

21N.1A.SL.TZ0.2

3.00 mol of C₃H₈ is mixed with 20.00 mol of O₂. Which quantity is present at the end of the reaction?

C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O (g)

A. 1.00 mol of C₃H₈

B. 5.00 mol of O₂

C. 12.00 mol of CO₂

D. 16.00 mol of H₂O

[1]

Markscheme

B

Syllabus sections

Structure 1. Models of the particulate nature of matter » Structure 1.4—Counting particles by mass: The mole » Structure 1.4.6—Avogadro’s law states that equal volumes of all gases measured under the same conditions of temperature and pressure contain equal numbers of molecules. Solve problems involving the mole ratio of reactants and/or products and the volume of gases.