Question

The only liquid which is a good conductor of heat is
A. water.
B. turpentine.
C. alcohol.
D. mercury.

Answer 1

Hint: We know that conduction is a property of materials to conduct or transfer energy. Thermal conduction is the transfer of energy by collisions of particles or electrons within the body. The energy transferred by collision is the sum of kinetic and potential energy or internal energy.

Complete step by step answer:
According to the thermal properties of matter, mercury is the only liquid good conductor of heat. That is why it is also used in a mercury thermometer.
We know that most metals are good conductors of heat as solid at room temperature. But mercury is the only good conductor of heat in a liquid state due to its high coefficient of expansion.
One more property of mercury that is its high boiling point makes it suitable for measuring high temperatures.
Hence the correct option is D.

Additional Information
Anomalous expansion of water: we know all liquid expands on heating but water behaves in anomalous behavior. When water is heated at 0 degrees Celsius its volume decreases and density increases till its temperature reaches 4 degrees Celsius. After reaching 4 degrees Celsius its density decreases and volume increases. Thus water at 4 degrees Celsius has maximum density.

Note:
We know that when liquid is heated its container also expands. The observed expansion of the liquid is called apparent expansion which is different from the real expansion of the liquid.
Coefficient of real expansion: It is defined as the real increase in volume per unit original volume for 1 degree Celsius rise in temperature.
Coefficient of apparent expansion: It is defined as the apparent increase in volume per unit original volume for 1 degree Celsius in temperature.