Answer:
RbNO3
Rb2SO4
Rb3PO4
Explanation:
Rubidium belongs to group 1 in the periodic table. All elements of group 1 have a valency of one.
They are highly reactive and only form compounds in which they are found in +1 oxidation state.
Hence, in all these compounds the oxidation state of rubidium is +1 as shown above.