Question

Benzamide can be preapred by the action of concentrated ammonia upon benzoyl chloride.
`underset("Benzoyl chloride")(C_(6)H_(5)COl)+2NH_(3) to underset("Benzamide")(C_(6)H_(5)_CONH_(2))+NH_(4)Cl`
In such experiment 65cc of concentrated ammonia (in excess) was treated with 15g of benzoyl chloride to give 11.1g of pure benzamide. Molar masses: benzoyl chloride (141), (benzamide)(121). The percentage yield of benzamide is:
A. `(11.1)/(15)xx100`
B. `((15-11.1))/(15xx100)`
C. `(11.1)/(65)xx100`
D. `(121)/(141)xx100`

Answer 1

Actual amount of benzamide formed=11.1g
`"% yield"=("Actual amount of product")/("Calculated amount of product")xx100`
`=(11.1xx100)/(((121)/(141)xx15))=(11.1xx141)/(121xx15)xx100`