Two important ores of metals are given below
Malachite `CuCO_(3).Cu(OH)_(2).xH_(2)O`
Carnallite `KCl.MgCl_(2).yH_(2)O`
What is y-x?

KCl.MgCl_2. 6H_2O is a

2CuCO_(3).Cu(OH)_(2) is the formula of

White vitriol is ZnSO_(4).xH_(2)O .What is x ?

The most important copper oxide containing minerals are azurite {Cu_(3)(OH)_(2)(CO_(3))_(2)} , malachite {Cu_(2)(OH)_(2)(CO_(3))} , cuprite (Cu_(2)O) , tenorite (CuO) . Extraction of copper from these low grade ores involves leaching followed by reduction Malachite ("leached")/("with bacteria") ("solution") Cu can be extracted from solution on treatment with:

The most important copper oxide containing minerals are azurite {Cu_(3)(OH)_(2)(CO_(3))_(2)} , malachite {Cu_(2)(OH)_(2)(CO_(3))} , cuprite (Cu_(2)O) , tenorite (CuO) . Extraction of copper from these low grade ores involves leaching followed by reduction. Some Cu is obtained just on leaching by dil H_(2)SO_(4) in :

The most important copper oxide containing minerals are azurite {Cu_(3)(OH)_(2)(CO_(3))_(2)} , malachite {Cu_(2)(OH)_(2)(CO_(3))} , cuprite (Cu_(2)O) , tenorite (CuO) . Extraction of copper from these low grade ores involves leaching followed by reduction "Azurite" overset(H_(2)SO_(4)(aq))rarrunderset((A))("solution") overset(KCN)rarrpptooverset(KCN)underset((excess))rarrunderset((B))("solution ") Select the INCORRECT statement:

The electrolysis of molten KCl. MgCl_(2) . 6H_(2)O gives