Question

If a student's unknown is a colorless liquid and its boiling point was measured to be about 78°C, it is most likely _______.
A.
phosphoric acid
B.
sodium hydroxide
C.
water
D.
ethanol

Answers

GPT-4o mini
The boiling point of the unknown colorless liquid measured at about 78°C is most consistent with ethanol, which has a boiling point of approximately 78.37°C.

The other options have different properties:
- Phosphoric acid has a high boiling point (around 158°C for its pure form).
- Sodium hydroxide is typically found as a solid and does not have a boiling point in its common form as a solution, which would be high.
- Water has a boiling point of 100°C at standard atmospheric pressure.

Therefore, the answer is most likely **D. ethanol**.