Chlorine has an atomic number of 17. How many protons are in
the nucleus of a chlorine atom?

17 protons

Explanation:

An element with 17 protons will always be chlorine. However an element's mass numbers can vary, which means that it can have different numbers of neutrons. So although chlorine has a mass number of 35 which means it has 18 neutrons, it can also have a mass number of 37, which means it has 20 neutrons.

1 a

2 d

3 a

4 c

explanation:

because u need two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei to form isotopes.

so since they all have the same shape? i mean maybe because m& m and reeses are both chocolates