Question

Which of the following are isotopes of the sulphur? 1=16p+16n 2=16n+17n 3=19p+16n 4=16p+17n

Answer 1

1 and 4

Explanation:

Sulphur has atomic number 16, which means it has 16 protons.
(1) would be called S-32 (most common)
(4) would be called S-33

As for the others:
(2) the nuleus would consist of only neutrons (not very likely)
(3) has 19 protons, and would be called K-35 (potassium), if it existed.