Question

the atomic mass of gold (au) is 198, and the atomic number of gold is 79. how many neutrons does a neutral atom of gold contain?
a. 99
b. 119
c. 79
d. 198

Explanation:

Step1: Recall neutron calculation formula

Neutrons = Atomic mass - Atomic number

Step2: Substitute values

Neutrons = $198 - 79 = 119$

Answer:

B. 119