Alcohol measurement — Proof equivalence: 95% (v/v) ethanol corresponds to how many proof degrees (U.S. system)?

Introduction / Context:
The “proof” scale is frequently used in distillation and ethanol handling. Converting between % alcohol by volume (ABV) and proof is a straightforward calculation yet commonly tested.

Given Data / Assumptions:

• U.S. proof definition: proof = 2 * ABV.
• ABV given: 95%.

Concept / Approach:
Apply the linear relation between ABV and proof for the U.S. system. No temperature correction is required for this conceptual question.

Step-by-Step Solution:
Let ABV = 95. Compute proof = 2 * 95 = 190. Match to the listed option.

Verification / Alternative check:
Everclear 95% ethanol is marketed as 190 proof, confirming the conversion.

Why Other Options Are Wrong:

• 110/120/170 proof: inconsistent with the 2 * ABV rule.

Common Pitfalls:
Confusing U.S. proof with historical U.K. proof (different scale) or using % w/w instead of % v/v.

Final Answer:
190 proof