DP Chemistry (first assessment 2025)
Question 19M.1A.SL.TZ2.22
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.1A.SL.TZ2.22 |
| Level | SL | Paper | 1A | Time zone | TZ2 |
| Command term | Question number | 22 | Adapted from | N/A |
22.
[Maximum mark: 1]
19M.1A.SL.TZ2.22
Consider the following electrochemical cell.
What happens to the ions in the salt bridge when a current flows?
A. Na+ ions flow to the zinc half-cell and SO42− ions flow to the copper half-cell.
B. Na+ ions flow to the copper half-cell and SO42− ions flow to the zinc half-cell.
C. Na+ and SO42− ions flow to the copper half-cell.
D. Na+ and SO42− ions flow to the zinc half-cell.
[1]
Markscheme
B
Examiners report
A challenging question about direction of ion flow in a salt bridge. 60 % answered correctly and the option with the opposite directions of flow of ions (A) was the most commonly chosen distractor.
Syllabus sections
Reactivity 3. What are the mechanisms of chemical change? » Reactivity 3.2—Electron transfer reactions » Reactivity 3.2.8—An electrolytic cell is an electrochemical cell that converts electrical energy to chemical energy by bringing about non-spontaneous reactions. Explain how current is conducted in an electrolytic cell. Deduce the products of the electrolysis of a molten salt.