Question

Quantity of 1.5g brass containing Cu,Zn reacts with `3M,HNO_(3)` solution, the following reactions takes place
`Cu +HNO_(3) rarr Cu^(2+) +NO_(2) +H_(2)O`
`Zn +H^(+) +NO_(3)^(-) rarr NH_(4)^(+) +ZN^(2+) +H_(2)O` (un balanced)
The liberated `NO_(2)(g)` is found to occupy 1.04 litre at `25^(@)C` and 1 atm pressure. Now answer the following question
% of copper in the alloy is
A. `9.56`
B. `14.34`
C. `6.37`
D. `19.12`

Answer 1

Correct Answer - B
`Cu + 4HNO_(3) rarr Cu (NO_(3))_(2) +2NO_(2) +2H_(2)O`
`4Zn + 10 HNO_(3) rarr NH_(4)NO_(3) +4Zn (NO_(3))_(2) +3H_(2)O`