Question

An elixir contains 47 % v/v alcohol, what is the proof spirit according to USP:

• A. 70%
• B. 82%
• C. 63%
• D. 91%

Hint:

In USP, proof is calculated as twice the percentage of alcohol by volume. Therefore, a \(47\%\) v/v alcohol elixir corresponds to approximately \(82\%\) proof spirit.

Answer 1

The Correct Option is B

The proof spirit is twice the percentage of alcohol by volume. Since the elixir contains \(47\%\) v/v alcohol, the corresponding proof spirit is 94 proof \((47\% 2)\). According to the USP, \(82\%\) alcohol corresponds to a 94 proof spirit (which is approximately double the percentage of alcohol content).