DP Chemistry (last assessment 2024)
Question 17N.2.sl.TZ0.5b.ii
| Date | November 2017 | Marks available | [Maximum mark: 1] | Reference code | 17N.2.sl.TZ0.5b.ii |
| Level | sl | Paper | 2 | Time zone | TZ0 |
| Command term | State | Question number | b.ii | Adapted from | N/A |
b.ii.
[Maximum mark: 1]
17N.2.sl.TZ0.5b.ii
The equations for two acid-base reactions are given below.
HCO3– (aq) + H2O (l) H2CO3 (aq) + OH– (aq)
HCO3– (aq) + H2O (l) CO32– (aq) + H3O+ (aq)
(b.ii)
State what is meant by the term conjugate base.
[1]
Markscheme
species that has one less proton/H+ ion «than its conjugate acid»
OR
species that forms its conjugate acid by accepting a proton
OR
species that is formed when an acid donates a proton
Do not accept “differs by one proton/H+ from conjugate acid”.
