See image — Hydrocarbons Chemistry Question

💡 Solution & Explanation

Concept: Calcium carbide (CaC2) reacts with water to produce acetylene (C2H2) and calcium hydroxide Ca(OH)2. When heavy water (D2O) is used instead of ordinary water, the deuterium atoms replace the hydrogen atoms in the products. Step 1: Write the normal reaction with ordinary water: CaC2 + 2H2O --> C2H2 + Ca(OH)2 Step 2: Replace H2O with D2O (heavy water): CaC2 + 2D2O --> C2D2 + Ca(OD)2 Step 3: Identify the products. The two products are C2D2 (deutero-acetylene) and Ca(OD)2 (calcium deuteroxide). The question asks for 'the product,' and among the given options, Ca(OD)2 is listed as option (c). Step 4: Evaluate why other options fail: - (a) C2H2: This would be the product if ordinary water were used, not heavy water. The carbon-bound hydrogens in acetylene come from the carbide (C2^2-), and in heavy water reaction the acidic D from D2O replaces to give C2D2, not C2H2. - (b) CaD2: This is not a product of this reaction; calcium carbide does not produce a calcium deuteride here. - (d) CD4: Methane (or deutero-methane) is not produced in this reaction; calcium carbide with water gives acetylene, not methane. Ca(OD)2 is indeed one of the correct products of the reaction between calcium carbide and heavy water. Therefore, the correct answer is C.