(i) To separate butter from curd, we can use the technique of churning. Churning agitates the curd, causing the fat globules to clump together and separate from the liquid portion, resulting in the formation of butter.
(ii) To separate salt from seawater, we can use the process of evaporation. Seawater is heated to allow the water to evaporate, leaving behind the salt as residue.
(iii) To separate camphor from salt, we can use the technique of sublimation. Camphor can sublime, meaning it can change directly from a solid to a vapor without passing through the liquid phase. By heating the mixture gently, the camphor will sublime, leaving behind the salt.