Calcium carbide on hydrolysis forms — Hydrocarbons Chemistry Question

💡 Solution & Explanation

# Hydrolysis of Calcium Carbide **Step 1: Identify the compound** Calcium carbide is $CaC_2$, containing the carbide ion $C_2^{2-}$ (acetylide ion). **Step 2: Write the hydrolysis reaction** $$CaC_2 + 2H_2O \rightarrow Ca(OH)_2 + C_2H_2$$ **Step 3: Identify the products** - **$Ca(OH)_2$** (calcium hydroxide) — a solid white precipitate - **$C_2H_2$** (ethyne/acetylene) — a colorless gas with a characteristic pungent odor **Step 4: Why this occurs** The $C_2^{2-}$ ion is a strong conjugate base and readily abstracts protons from water molecules, producing acetylene gas and hydroxide ions. **Conclusion:** The hydrolysis of calcium carbide produces **calcium hydroxide and acetylene (ethyne)**, which is option D. *Note: The acetylene gas is easily identified by its sharp, unpleasant smell and is historically used in welding/cutting torches.*