Question

​Increase of pressure, which are true:
1. Always increase the boiling point of liquid.
2. Always increase the melting point of solid.
3. increase the melting point of solids which expands on melting .
4. Always decreases the melting point of solids.
Options are:
A. 1 and 2
B.1 and 4.
C.1 and 3.
​D. 1, 2 and 3

Answer 1

Dear Student.

The boiling point of a liquid varies depending upon the surrounding environmental pressure. A liquid in a partial vacuum has a lower boiling point than when that liquid is at atmospheric pressure. A liquid at high pressure has a higher boiling point than when that liquid is at atmospheric pressure.

1 is true from the above explanation.
if you increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point
4 is true from above explanation.
1 and 4 are true.

Regards