Question

The melting point of ice can fluctuate due to various reasons. Pick the correct reasons from the following:

• A. It decreases with increase in altitude.
• B. It decreases with increase in pressure.
• C. It increases with the addition of impurities.
• D. It decreases with the addition of impurities.

Answer 1

Answer: (B), (D)

The correct options are
B It decreases with increase in pressure.
D It decreases with the addition of impurities.

As ice contracts on melting, an increase in pressure helps the phase change and thus requires less energy for the change. This is the reason why the melting point reduces, as the pressure increases. The addition of impurities also decreases the melting point of ice.