For heavy elements, what is the ratio of neutrons to protons that predicts a stable nucleus?

A.

1:1

B.

1.5:1

C.

2:1

D.

10:5

B. 1.5:1

Explanation:

Let's take mercury (Hg) for an example.

Mercury have proton number of 80 and neutron number of 121.

To know the ration, you need to divide the neutron number with the proton number.

121/80

=1.5/1

Then, change the answer to ratio form=1.5:1