Both sections of the chemistry paper score +4 for a right answer, -1 for a wrong one and 0 for a question left unanswered.
| Right answer | +4 |
|---|---|
| Wrong answer | -1, in Section A and Section B |
| Unanswered | 0 |
| Section B entry | An integer, on an on-screen keypad |
In Section B you enter the answer as an integer with the mouse and an on-screen numeric keypad. The bulletin says the answer should be rounded off to the nearest integer.
A pure guess on a four-option question is right one time in four, so on average it is worth 1/4 × 4 − 3/4 × 1 = 1/4 of a mark. Rule out one option and the average rises to 1/3 × 4 − 2/3 × 1 = 2/3 of a mark. An average is not a promise: each wrong guess still costs a mark, so solve what you can first and guess only after ruling options out.
Our two timed papers use the same rule: +4, -1 and 0, for 20 multiple-choice and 5 numerical questions in 60 minutes. The result is marks out of 100 by section, never a percentile or a rank.
Yes. The 2027 bulletin gives -1 for an incorrect answer in Section B as well as Section A.
The bulletin says that if a question is found to be incorrect or is dropped, every candidate in that shift gets 4 marks for it.