Short Quiz

Which of the following gases can be used for storage of fresh samples of an oil for a long time?

Which of the following are combination reactions?
(i) \(2 \mathrm{KClO}_3 \xrightarrow{\text { Heat }} 2 \mathrm{KCl}+3 \mathrm{O}_2\)
(ii) \(\mathrm{MgO}+\mathrm{H}_2 \mathrm{O} \longrightarrow \mathrm{Mg}(\mathrm{OH})_2\)
(iii) \(4 \mathrm{Al}+3 \mathrm{O}_2 \longrightarrow 2 \mathrm{Al}_2 \mathrm{O}_3\)
(iv) \(\mathrm{Zn}+\mathrm{FeSO}_4 \longrightarrow \mathrm{ZnSO}_4+\mathrm{Fe}\)

Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of the reaction involved?
(i) Displacement reaction
(ii) Precipitation reaction
(iii) Combination reaction
(iv) Double displacement reaction

Which among the following is(are) double displacement reaction(s)?
(i) \(\mathrm{Pb}+\mathrm{CuCl}_2 \rightarrow \mathrm{PbCl}_2+\mathrm{Cu}\)
(ii) \(\mathrm{Na}_2 \mathrm{SO}_4+\mathrm{BaCl}_2 \rightarrow \mathrm{BaSO}_4+2 \mathrm{NaCl}\)
(iii) \(\mathrm{C}+\mathrm{O}_2 \rightarrow \mathrm{CO}_2\)
(iv) \(\mathrm{CH}_4+2 \mathrm{O}_2 \rightarrow \mathrm{CO}_2+2 \mathrm{H}_2 \mathrm{O}\)