0.76 g of a silver salt of a dibasic acid on ignition gave 0.54 g of silver. Calculate the molecular mass of the acid.

Explanation

Mass of the silver salt taken = 0.500 g
Mass of silver residue = 0.3254 g
Suppose, the equivalent mass of the given acid is E. Since,
`("Eq. mass of silver salt ")/(Eq. mass of silver ") =("Mass of the silver salt taken")/(" Mass of silver residue ")`
we have,
` (E + 107 ) /( 108 ) = ( 0.500 )/(0.3254 )`
` therefore E= ((0.500 )/(0.3254 ) xx 108 )- 107 = 58.95`
Molecular mass of the acid
= Equivalent mass `xx` Basicity
`= 58.95 xx 2 = 117.9`
Hence, the molecular mass of the given acid is 117.9.