NCERT In-text Q2 (Section 1.1) - Chemical Reactions and Equations
Question: A solution of substance 'X' is used for whitewashing. (i) Name the substance 'X' and write its formula. (ii) Write the reaction of substance 'X' with water.
Answer: X = Calcium Oxide (CaO) — Quick Lime. Reaction: CaO(s) + H2O(l) → Ca(OH)2(aq) + Heat. This is an exothermic combination reaction producing slaked lime.
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