Matching Column Type

Answer

A-p; B-q; C-p,r ; D-p,s

Explanation

For PbO , roasting is done
For `CaCO_3 rarr CaO,` Calcination is done in the absence of air.
For `ZnS rarr Zn`, there is roasting followed reduction.
`2ZnS + 3O_2 rarr 2ZnO + 2SO_2 uarr`
`ZnSO_4 overset(Delta) rarr ZnO +SO_2 + 1/2 O_2 uarr`
`ZnO + C overset(Delta) rarr Zn + CO uarr`