determine the empirical formula of rubidium sulfide.

The empirical formula of a compound gives the simplest whole number ratio of atoms of each element in the compound.

1. Identify the symbol of each element: Rubidium (Rb) and Sulfur (S).

2. Identify the charge of each ion: Rubidium is in group 1 of the periodic table and forms a +1 ion (Rb+). Sulfur is in group 16 of the periodic table and forms a -2 ion (S2-).

3. Balance the charges to get a neutral compound: We need two +1 rubidium ions to balance one -2 sulfur ion.

So, the empirical formula of rubidium sulfide is Rb2S.