Answer
$C_9H_{7}O_3Mn$
Work Step by Step
Atomic weights (g/mol):
$C: 12.011, \ H: 1.008,\ O: 15.999,\ Mn: 54.938$
In 100 g :
C: $49.5\ g \div 12.011 \ g/mol=4.12\ mol$
H: $3.2\ g\div1.008\ g/mol=3.17\ mol$
O: $22.0\ g\div15.999\ g/mol=1.38\ mol$
Mn: $25.2\div54.938\ g/mol=0.46\ mol$
Dividing all these number of moles by the smallest value (0.46) leads to the empirical formula:
C: $4.12\div0.46=9.0$
H: $3.17\div0.46=7.0$
O: $1.38\div0.46=3.0$
$C_9H_{7}O_3Mn$
