Four metals `P, Q, R` and `S` are all obtained by the reduction of their oxides with carbon. Metal `P` is used to form a thin layer over the sheets of metal `S` to prevent its corrosion. Metal `Q` is used for electroplating tiffin boxes made of metal `S` whereas metal `R` is used in making car batteries. Metals `Q` and `R` form an alloy called solder. what are metals `P,Q,R` and `S` ? How have you arrived at this conclusion ?

Explanation

1) Metal `P` is zinc

2) Metal `Q` is tin, metal `R` is lead
3) Metal `S` is iron metal `P` (zinc) is used to form a thin layer on metal `S` (iron) to prevent its corrosion.
4) Metal `Q` (tin) is used for electroplating tiffin boxes made of metal `S` (iron)
5) Metal `R` (lead) is used in making car batteries.
6) Metals `Q` (tin) and `R` (lead) form an alloy called solder.