Answer:
The nucleus of a sulfur atom contains 16 protons.
The nucleus of a chlorine atom contains 17 protons.
Step-by-step explanation:
Atoms are arranged in the Periodic Table according to the number of protons in their nuclei — their atomic numbers.
A proton is an integral particle — you can't have half a proton.
S and Cl are adjacent in the Periodic Table, so it is impossible to find an element that will fit between them.