The liquids A and B boil at 145°C and 190°C respectively. Which of them has a higher vapour pressure at 80°C?
Answer: A — the lower-boiling liquid is more volatile, so it has the higher vapour pressure.
Solution
The liquid with the lower boiling point is more volatile.
A boils at 145°C (< 190°C), so at 80°C liquid A has the higher vapour pressure.
A boils at 145°C (< 190°C), so at 80°C liquid A has the higher vapour pressure.
CBSE Class 12 Board · 2006 · Delhi · Subjective