Question

100 percent pure ethanol is called :

• A. Rectified spirit
• B. Absolute alcohol
• C. Denatured alcohol
• D. Power alcohol

Hint:

Do not confuse absolute alcohol with rectified spirit.
- Rectified spirit = \(95.6\%\) pure (azeotrope).
- Absolute alcohol = \(100\%\) pure (water-free).

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
The question asks for the specific terminology used to describe ethanol that is 100 percent pure and free of water.

Step 2: Key Formula or Approach:
We distinguish between different commercial grades of ethanol.

Step 3: Detailed Explanation:

• Let us define the terms:
- Rectified Spirit: This is a mixture containing approximately \(95.6\%\) ethanol and \(4.4\%\) water by volume. It is an azeotropic mixture, meaning it cannot be concentrated further by simple distillation.
- Absolute Alcohol: This is the chemical term for highly purified, water-free ethanol that is at least \(99\%\) to \(100\%\) pure. It is obtained by special dehydrating distillation processes.
- Denatured Alcohol: This is ethanol that has toxic or unpalatable additives (like methanol, pyridine, or copper sulfate) added to make it unfit for human consumption, primarily to avoid beverage taxes.
- Power Alcohol: This is a blend of absolute alcohol and petrol used as fuel for internal combustion engines.

• Thus, 100 percent pure ethanol is specifically called absolute alcohol.


Step 4: Final Answer:
100 percent pure ethanol is called absolute alcohol.