Which of the following is(are) an endothermic process(es)?
$(i)$ Dilution of sulphuric acid
$(ii)$ Sublimation of dry ice
$(iii)$ Condensation of water vapours
$(iv)$ Evaporation of water

Write true or false for the following statement:
Due to corrosion, iron gets a brown coating, copper gets a green coating, and silver gets a black coating.

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

Grapes hanging on the plant do not ferment,but after being plucked from the plant,they can be fermented. Under what conditions do these grapes ferment? Is it a chemical or a physical change?

Ferrous sulphate decomposes with the evolution of a gas having a characteristic odour of burning sulphur. Write the chemical reaction involved and identify the type of reaction.

Which two observations will be made when quicklime is added to water? Mention two uses of the product obtained.