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 :

Copper metal can be prepared by roasting copper ore, which contain cup

1.	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 :
Answer» 0.448 0.2 0.224 0.4 Solution :`{:(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 %`