How many atoms of s are there in one molecule of sh4?

one.

Explanation:

Let us break it up

Just take away. the four for now. After the four is gone, you would see onlly two atoms, one of the two is well... S. That gets you your answer.

(The 4 does not apply to the S, the 4 only applies to the H since it comes after not before.)

give me abc and i will get it for u.

you need to have a picture of the atom that way we can answer it