Question

The mass number of a neutral atom of potassium (z=19) is 40 How many electrons does it have?

Which characteristic of the nuclear force explains why the helium nucleus is exceptionally stable?

Answer 1

Step-by-step explanation:

Two

The nuclear force does not work

under long distances

is greater in strength the the electomagnetic force when the distances are small.

I'm not sure what D means.

I think it does depend on charge.

You have to choose D but this is a notes question and I'm not at all certain of the answer.

One

If its number is 19, the the number of protons = the number of electrons = 19

Answer B