Which reactions are used for the preparation of halogen acids?

CHEMISTRY · Multi correct

Problem

Which reactions are used for the preparation of halogen acids? (1)

2\text{KBr}+\text{H}_2\text{SO}_4\xrightarrow{\text{conc.}}\text{K}_2\text{SO}_4+2\text{HBr}

(2)

\text{CaF}_2+\text{H}_2\text{SO}_4\xrightarrow{\text{conc.}}\text{CaSO}_4+2\text{HF}

(3)

\text{NaCl}+\text{H}_2\text{SO}_4\xrightarrow{\text{conc.}}\text{NaHSO}_4+\text{HCl}

(4)

2\text{KI}+\text{H}_2\text{SO}_4\xrightarrow{\text{conc.}}\text{K}_2\text{SO}_4+2\text{HI}