To determine the oxidation number of rubidium, we know that the overall charge of the compound is neutral. Since chlorine has an oxidation number of -1 and oxygen has an oxidation number of -2, the sum of their oxidation numbers must be equal to the positive charge of rubidium.
Let x be the oxidation number of rubidium. We can set up the equation:
x + (-1) + (-2) = 0
Solving for x, we get:
x = +1
Therefore, the oxidation number of rubidium (Rb) in RbClO is +1.
