Question

the isotope of an atom containing 40 protons and 51 neutrons suddenly has two neutrons added to it. what isotope is created?
o antimony-53
o zirconium-93
o zirconium-53
o antimony-03

Explanation:

Step1: Identify element by protons

The number of protons determines the element. 40 protons means the element is zirconium (Zr).

Step2: Calculate new mass - number

Initial number of neutrons is 51, 2 more neutrons are added, so new number of neutrons is $51 + 2=53$. Mass - number = number of protons+number of neutrons. So mass - number is $40+53 = 93$. The isotope is Zirconium - 93.

Answer:

B. Zirconium - 93