| Date | November 2014 | Marks available | 1 | Reference code | 14N.1.SL.TZ0.24 |
| Level | Standard level | Paper | Paper 1 | Time zone | Time zone 0 |
| Command term | Question number | 24 | Adapted from | N/A |
Question
In a neutral atom there are ne electrons, np protons and nn neutrons. What is the mass number of the nuclide?
A. np + ne + nn
B. np + nn
C. nn + np – ne
D. nn – ne
Markscheme
B
Examiners report
[N/A]
Syllabus sections
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