How many neutrons are present in atom with mass number and atomic number 37 and 17 respectively?

A. 18
B. 20
C. 37
D. 17

Correct Answer:

Option B = 20

Explanation

The mass number = number of neutrons + atomic number.

number of neutrons = The mass number – atomic number.

number of neutrons = 37 – 17 = 20