Answer:
CrO₃.
Step-by-step explanation:
We'll begin by calculating the percentage of chromium in the oxide. This can be obtained as follow:
Oxygen (O) = 48%
Chromium (Cr) =?
Oxide of chromium contains only chromium and oxygen. Therefore, the percentage of chromium in the oxide is given by:
Cr = 100 – percentage of oxygen
Cr = 100 – 48
Cr = 52%
Finally, we shall determine the empirical formula of the oxide as follow:
Chromium (Cr) = 52%
Oxygen (O) = 48%
Divide by their molar mass
Cr = 52/52 = 1
O = 48/16 = 3
Divide by the smallest
Cr = 1/1 = 1
O = 3/1 = 3
Therefore, the empirical formula of the oxide is CrO₃.