Reduction of 90 g of acetaldehyde with hydrogen gave 82 g of ethyl alcohol. Determine the mass fraction of the alcohol yield.

| April 29, 2021 | education

1. CH3CHO + H2 → CH3CH2OH;

2. the initial reagent was an aldehyde, which means that all calculations from the data on it will be theoretical. Let’s find its chemical amount:

ntheor (CH3CHO) = m (CH3CHO): M (CH3CHO);

M (CH3CHO) = 12 + 3 + 12 + 1 + 16 = 44 g / mol;

ntheor (CH3CHO) = 2.045 mol;

3.the theoretical amount of ethanol will correspond to the amount of aldehyde:

ntheor (CH3CH2OH) = ntheor (CH3CHO) = 2.045 mol;

4. calculate the practical chemical amount according to the data for the reaction product:

ntrap (CH3CH2OH) = m (CH3CH2OH): M (CH3CH2OH);

M (CH3CH2OH) = 12 + 3 + 12 + 2 + 16 + 1 = 46 g / mol;

npt (CH3CH2OH) = 82: 46 = 1.783 mol;

5.Let’s find the alcohol output:

ν (CH3CH2OH) = ntract (CH3CH2OH): ntheor (CH3CH2OH);

ν (CH3CH2OH) = 1.783: 2.045 = 0.8719 or 87.19%.

Answer: 87.19%.



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.