Question

what is the atomic symbol and mass number for an atom containing 88 protons and 138 neutrons?

Explanation:

Step1: Determine the atomic symbol

The element with 88 protons is Radium, symbol Ra.

Step2: Calculate the mass number

Mass number = number of protons + number of neutrons. Given protons = 88 and neutrons = 138, mass number = \(88 + 138=226\)

Answer:

\(^{226}\text{Ra}\)