Chemistry
Grade-9
Easy
Question
What is the mass number of this atom?
- 1
- 3
- 4
- 7
Hint:
Mass number = number of protons + number of neutrons.
The correct answer is: 7
- Atomic number = number of protons.
- Mass number = number of protons + number of neutrons.
- In the given picture there are 3 protons, 3 electrons and 4 neutrons.
- The mass number is 7.
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