DP Chemistry (last assessment 2024)

Test builder »

Question 19M.1.sl.TZ1.19

Select a Test
Date May 2019 Marks available [Maximum mark: 1] Reference code 19M.1.sl.TZ1.19
Level sl Paper 1 Time zone TZ1
Command term Question number 19 Adapted from N/A
19.
[Maximum mark: 1]
19M.1.sl.TZ1.19

Which solution is basic at 25 °C?

Kw = 1.0 × 10−14

A. [H+] = 1.0 × 10−3 mol dm−3

B. [OH−] = 1.0 × 10−13 mol dm−3

C. solution of pH = 4.00

D. [H3O+] = 1.0 × 10−13 mol dm−3

[1]

Markscheme

D

Examiners report

This was very poorly answered and had one of the highest discriminatory indices. More candidates thought that a basic solution would have [OH- ] = 1.0 x 10-13 mol dm-3 , rather than [H3O+ ] = 1.0 x 10-13 mol dm-3

Syllabus sections