Cobalt is element 27.Cobalt-60 is used in the medical treatment of cancer.How many neutrons and protons are contained in the nucleus of this isotope?
A)27 neutrons,33 protons
B)33 neutrons,27 protons
C)27 neutrons,27 protons
D)33 neutrons,33 protons
E)60 neutrons,27 protons

Question

Quizplus · Accepted Answer

The atomic number of Cobalt is 27, which means it has 27 protons. 
Cobalt-60 is an isotope, which means it has the same number of protons as regular cobalt (27), but a different number of neutrons. 
To find the number of neutrons, we subtract the atomic number from the mass number. 
The mass number of Cobalt-60 is 60, so the number of neutrons is 60-27=33. 
Therefore, the correct answer is B, which states that Cobalt-60 contains 33 neutrons and 27 protons.

Cobalt Is Element 27