what happens when dilute suphuric acid is treated with:
(a) Fe (b) `CaF_(2)` ?

Explanation

(i) when dilute sulphuric acid is treated with Fe, `FeSO_(4)` is formed and hydrogen gas is released:
`Fe + H_(2) SO_(4) to FeSO_(4) + H_(2)`
(ii) Calcium fluoride reacts with sulphuric acid to produce hydrogen fluoride and calcium sulphate Heating the reaction mixture to the temperature of `130^(@)- 200^(@)C`
`CaF_(2) + H_(2) SO_(4) overset(130 - 200^(@)C)(to) 2HF + CaSO_(4)`