Answer:
The empirical formula of the compound is
.
Explanation:
Mass of chromium = 19.13 g
Mass metal bromide formed = 77.92 g
Mass of bromine in metal bromide = 77.92 g - 19.13 g = 58.79 g
Moles of chromium metal :

Moles of bromine:

For empirical formula divide the smallest number of moles of element from the all the moles of elements:
chromium : 
bromine : 
The empirical formula of the compound is
.