Urea `(H_(2)NCONH_(2))` is manufactured by passing `CO_(2) (g)` through ammonia solution followed by crystallization. `CO_(2)` for the above reaction is prepared by combustion of hydrocarbon. If combustion of 236kg of a saturated hydrocarbon `(C_(n)H_(2n+2))` produces as much `CO_(2)` as required for production of `999.6 kg` urea then molecular formula of hydrocarbon is : `C_(10)H_(22)`, `C_(12)H_(26)`, `C_(13)H_(28)`, `C_(8)H_(18)`,

Options

A. `C _(10) H _(22)`
B. `C _(12) H _(26)`
C. `C _(13) H _(28)`
D. `C _(8) H _(18)`

Answer

B

Explanation

`2 NH _(3) + CO _(2) to NH _(2) - CO - NH _(2) + H _(2) O`
moles of ures `= ( 999 . 6 xx 10 ^(3))/( 60) = 16. 66 xx 10 ^(3) therefore ` mooles of `CO _(2) = 16.66 xx 10 ^(3)`
`C _(n) H _( 2n + 2) + (( 3n + 1)/(2)) O _(2) to n CO _(2) + (n + 1) H _(2) O`
`(16.66 xx 10 ^(3))/( n ) xx [ 12 n + ( 2n+ 2)]=236 xx 10 ^(3)`
`n ~~ 12 therefore` Molecular formula of hydrogen `= C _(12) H _(26)`