An atom of beryllium has 4 protons, 4 electrons, and 5 neutrons. What is its mass number?

Question

asked Apr 22, 2021 34.6k views

1 Answer

Dotminic · Answer 1 · 2021-04-27T15:10:56+0000

Answer:

D. 9.

Step-by-step explanation:

Mass number of an atom is the sum of the proton number and neutron number. For Be, the protons are 4 and neutrons are 5. So, we get 9 by adding them.