Question

The atomic mass of an atom is 28 and has 15 neutrons. What is its atomic number? a. 15 c. 13 b. 28 d. 43

Answer 1

Answer: Option C) The Atomic number is 13

Explanation:

The number of neutrons + Protrons = Atomic Mass

Thus, 15 + Protrons = 28

Protrons = 28 - 15 = 13

Usually, the number of protons in an atom is always EQUAL to the Atomic number of the atom

Since number of protons is 13, therefore the atomic number of the given atom is 13

Answer 2

Answer: C. 13

Explanation:

28 - 15 = 13

so therefore choice C is your answer