MHT CET202525 Apr 2025Morning ShiftChemistryHaloalkanes and HaloarenesActual
Calculate percentage atom economy when 46 g ethanol is obtained from 64.5 g chloroethane and 56 ~g~ KOH ( aq )
Options
- A25 25 %
- B38 17 %
- C50 25 %
- D64 17 %
Correct answer
B. 38 17 %
Step-by-step solution
The reaction proceeds by nucleophilic substitution: C₂H₅Cl + KOH C₂H₅OH + KCl Percentage atom economy evaluates the mass efficiency of the desired product formation: Percentage Atom Economy = Mass of desired product Total mass of all reactants 100 % Given 64.5 g chloroethane and 56 g potassium hydroxide produce 46 g ethanol, the total reactant mass sums to 120.5 g . The atom economy becomes: 46 120.5 100 % 38.17 % This result could be confirmed by computing the total product mass: 46 g ethanol + 74.5 g KCl = 120.5