The atomic number of krypton (Kr) is 36, and its mass number is 84. How many neutrons does it have?

i believe the answer is 48 neutrons

Answer: 48 neutrons

Explanation:

Mass number is defined as the sum of number of protons and neutrons that are present in an atom.

Mass number = Number of protons + Number of neutrons

Atomic number is defined as the number of protons or number of electrons that are present in an atom.

Atomic number = Number of electrons = Number of protons

Given: Atomic number of Krypton = Number of electrons = Number of protons = 36

Mass number of krypton = Number of protons + Number of neutrons = 84

Thus, 84 = 36 + Number of neutrons

Number of neutrons = 48

Thus krypton has 48 neutrons.