Question
The symbol below describes a nuclide.
Which row is correct?
| proton number (Z) | nucleon number (A) |
A | 4 | 5 |
B | 4 | 9 |
C | 9 | 4 |
D | 9 | 5 |
Answer/Explanation
Ans: B
Question
The charge on a proton is e.
What is the charge on an electron and what is the charge on a neutron?
| electron | neutron |
A | e | e |
B | e | 0 |
C | –e | –e |
D | –e | 0 |
Answer/Explanation
Ans: D
Question
Which statement about the structure of an atom is correct?
A Negative electrons surround a neutral nucleus.
B Negative electrons surround a positive nucleus.
C Positive electrons surround a neutral nucleus.
D Positive electrons surround a negative nucleus.
Answer/Explanation
Ans: B
Question
A nuclide of the element iron has the symbol shown.
What does a neutral atom of this nuclide contain?
| protons | neutrons | electrons |
A | 26 | 30 | 26 |
B | 26 | 56 | 30 |
C | 30 | 26 | 56 |
D | 56 | 26 | 30 |
Answer/Explanation
Ans: A
Question
In the atomic model, an atom consists of a central mass, orbited by much smaller particles.
What is the name of the central mass and of the orbiting particles?
| central mass | orbiting particles |
A | neutron | α-particles |
B C | neutron nucleus | electrons α-particles |
D | nucleus | electrons |
Answer/Explanation
Ans: D