DP Chemistry (last assessment 2024)

Question 18N.2.sl.TZ0.5b

Date	November 2018	Marks available	[Maximum mark: 3]	Reference code	18N.2.sl.TZ0.5b
Level	sl	Paper	2	Time zone	TZ0
Command term	Predict	Question number	b	Adapted from	N/A

[Maximum mark: 3]

18N.2.sl.TZ0.5b

This reaction is used in the manufacture of sulfuric acid.

2SO₂ (g) + O₂ (g) $\rightleftharpoons$ 2SO₃ (g) K_c = 280 at 1000 K

(b)

0.200 mol sulfur dioxide, 0.300 mol oxygen and 0.500 mol sulfur trioxide were mixed in a 1.00 dm³ flask at 1000 K.

Predict the direction of the reaction showing your working.

[3]

Markscheme

«reaction quotient/Q =» $\frac{{{{\left[ {{\text{S}}{{\text{O}}_3}} \right]}^2}}}{{{{\left[ {{\text{S}}{{\text{O}}_2}} \right]}^2}\left[ {{{\text{O}}_2}} \right]}}{\text{/}}\frac{{{{0.500}^2}}}{{{{0.200}^2} \times 0.300}}{\text{/}}20.8$ ✔

reaction quotient/Q/20.8/answer < K_c/280

mixture needs more product for the number to equal Kc ✔

reaction proceeds to the right/products ✔

Do not award M3 without valid reasoning.

Syllabus sections

Core

Core » Topic 7: Equilibrium » 7.1 Equilibrium

Core » Topic 7: Equilibrium

Question 18N.2.sl.TZ0.5b

Select a Test

Syllabus sections

Confirm action