Question

How many neutrons does an element have if its atomic number is 56 and its mass number is 243?

Answer 1

Answer:

187

Explanation:

atomic number = number of electrons or protons in a atom

atomic number = 56

Then, the number proton is 56

mass number = sum of the number of protons and no. of neutrons

mass number = 243

243= 56 + no. of neutrons

no.of neutrons = 243 - 56 = 187