Potassium sulphide (or sulfide to use the modern spelling) is made of potassium and sulfur.
The -ide ending tells you that there are only two elements there.
Potassium and sulfur
The two elements in potassium sulphide are potassium and sulpfur.
Potassium sulphide.
iron and sulfur
Potassium and nitrogen
KHS
DYUUNII
With the formula K2SO4, potassium sulfate contains the elements potassium, sulfur, and oxygen.
Potassium is an element by itself.
potassium sulphide
Potassium and Iodine
Ferrous refers to iron, and sulphide refers to sulfur.
Iron sulphide (FeS) is made of two elements, viz. Iron(Fe) & Sulphur(S).