A laboratory requires 100% pure ethanol for a sensitive reaction. Which substance is used to remove the last traces of water from rectified spirit?
Q1. A laboratory requires 100% pure ethanol for a sensitive reaction. Which substance is used to remove the last traces of water from rectified spirit?
Answer: CaO
Explanation: Absolute alcohol (100%) is obtained by redistilling rectified spirit with CaO, which absorbs the remaining water. Benzene is used for ternary azeotropes.