Which of the following are exothermic processes?
$(i)$ Reaction of water with quick lime
$(ii)$ Dilution of an acid
$(iii)$ Evaporation of water
$(iv)$ Sublimation of camphor (crystals)

$(a)$ Give an example of a combination reaction which is exothermic.
$(b)$ Identify the oxidizing agent and reducing agent in the following reaction:
$H_{2}S + Cl_{2} \rightarrow 2HCl + S$
$(c)$ Name the phenomenon due to which the taste and smell of oily food changes when kept for a long time in the open. Suggest one method to prevent it.

When air is blown from the mouth into a test tube containing lime water,the lime water turns milky due to the presence of:

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 balanced chemical equations for the following:
$(i)$ Carbon dioxide gas is passed through lime water.
$(ii)$ $NaOH$ solution is heated with zinc granules.

Which among the following statement$(s)$ is(are) true? Exposure of silver chloride to sunlight for a long duration turns grey due to
$(i)$ the formation of silver by decomposition of silver chloride
$(ii)$ sublimation of silver chloride
$(iii)$ decomposition of chlorine gas from silver chloride
$(iv)$ oxidation of silver chloride