Copper metal can be prepared by roasting copper ore, which contain cuprite `(Cu_(2)S)` and copper sulfide. (CuS) `Cu_(2)S (s) + O_(2) (g) rarr 2Cu (s)
Copper metal can be prepared by roasting copper ore, which contain cuprite `(Cu_(2)S)` and copper sulfide. (CuS)
`Cu_(2)S (s) + O_(2) (g) rarr 2Cu (s) + SO_(2) (g)`
`CuS (s) + O_(2) (g) rarr Cu (s) + SO_(2) (g)`
If ore contains 14.6% impurity in addition to a mixture of CuS and `Cu_(2)S`. Heating 100 gm of mixture produces 70 gm of Cu metal with 90% purity. `[Cu = 63]`
Percentage (By mass) of sulphur in the sample is :
A. 0.448
B. 0.2
C. 0.224
D. 0.4
1 Answers
Correct Answer - C
`{:(Cu_(2)S,+,O_(2) rarr,2Cu,+,SO_(2),),(a mol,,,2 a mol,,,),(CuS,+,O_(2) rarr,Cu,+,SO_(2),),(b mol,,,(b mol),,,):}`
`a xx 158 + b xx 95 = 85.4` …(i)
`(2a + b) xx 63 = (70 xx 90)/(100) = 63`
`2a + b = 1` …(ii)
`a = 0.3, b = 0.4`
% by mass of sulphur in sample `= ((0.3 + 0.4) 32 xx 100)/(100)`
`= 22.4 %`