250+ TOP MCQs on C2 Compounds-Ethanol and Answers

Chemical Technology Multiple Choice Questions on “C2 Compounds – Ethanol”.

1. Which enzyme is used to hydrolyse starch to maltose to manufacture ethanol by fermentation?
a) Diastase
b) Alpha-Amylase
c) Lipase
d) Beta-Amylase

Answer: a
Clarification: Diastase catalyses the breakdown of starch into maltose. Lipase is an enzyme that catalyses the hydrolysis of lipids. Amylase breaks down complex carbohydrates to starch.

2. Which among the following methods cannot be used for the manufacture of ethanol?
a) From fermentation of molasses
b) From lignocelluloses biomass
c) Catalytic hydrogenation of ethylene
d) From microorganisms

Answer: d
Clarification: Ethanol cannot be derived from microorganisms. The most widely used method for the manufacture of ethanol is from fermentation of molasses.

3. What is mash made up of in the manufacture of ethanol from molasses?
a) Ammonium nitrate + Magnesium nitrate
b) Ammonium nitrate + Magnesium nitrate + Phosphorous
c) Ammonium sulphate + Magnesium sulphate
d) Ammonium sulphate + Magnesium sulphate + Phosphorous

Answer: d
Clarification: Nutrients such as Ammonium sulphate, Magnesium sulphate and Phosphorous are added to molasses to support the yeast growth.

4. Denatured ethanol is safe for drinking.
a) True
b) False

Answer: b
Clarification: Denatured alcohol consists many additives which are harmful to the human body, such as methanol. So denatured ethanol is not safe for human consumption.

5. The pH of molasses solution in the manufacture of ethanol should be __________
a) 1-2
b) 2-3
c) 7-9
d) 4-5

Answer: d
Clarification: The pH of the molasses solution must be in the range of 4-5 to support yeast growth which furnishes invertase and zymase. pH is adjusted by adding sulfuric acid.