State what happens when:
$(a)$ Chlorine gas is passed through dry slaked lime.
Also write the chemical equation in each case.

Write the chemical equation of the reaction with an example in which a change in colour takes place.

Calcium oxide reacts vigorously with water to produce:

In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate,a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available,which of the following can be used in place of lead nitrate?

Balance the following chemical equation:
$Fe(s) + H_2O(g) \rightarrow Fe_3O_4(s) + H_2(g)$

Which of the following are combination reactions?
$(i)$ $2 KClO_{3} \xrightarrow{\text{Heat}} 2 KCl + 3O_{2}$
$(ii)$ $MgO + H_{2}O \longrightarrow Mg(OH)_{2}$
$(iii)$ $4 Al + 3O_{2} \longrightarrow 2 Al_{2}O_{3}$
$(iv)$ $Zn + FeSO_{4} \longrightarrow ZnSO_{4} + Fe$