Which of the following will increase the boiling point of water?
I. Taking it to a high altitude
II. Dissolving a salt into it
III. Heating it in a sealed flask
IV. Increasing the rate of heat supply
.
A
I only
B
III & IV only
C
II & III only
D
II only
Verified Correct Answer: C.
Physical Principles & Numerical Solution
The simplest way to change the boiling point of a liquid is to change the surrounding pressure. (a) Using a closed system to artificially increase that pressure will raise the boiling point of a liquid. (b) Boiling point is dependent upon the strength of the bonds between its molecules. For this reason, adding a solute to the liquid will create stronger bonds between molecules, raising the solution’s boiling point without increasing pressure.
Source: Myschool Past Questions Archive (Record #40886)