Question

Water is a bad conductor of heat because:
A. It has excess free electrons
B. It has high pH
C. It lacks free electrons
D. It has low pH

Answer 1

Hint: The heat conduction occurs when the heat energy gets transferred from the high temperature region to the low temperature region within the same material. The heat conduction generally occurs due to vibrations of electrons. Find out whether the water has excess electrons or deficiency of electrons.

Complete answer:
To answer this question, let us discuss the process of heat transfer through conduction. The heat conduction occurs when the heat energy gets transferred from the high temperature region to the low temperature region within the same material. When we heat a substance or liquid, the free electrons in the substance vibrates rapidly and transfers the heat energy to the adjacent electrons that they are colliding. Thus, we can say the more free electrons in the substance are more efficient are the heat transfer within the substance.

Now, we know that the electrons of water molecules are tightly bonded to the molecule. Therefore, when one layer of the water is heated, the electrons do not transfer the energy to the adjacent water molecules more efficiently as in the case of metals. In metals, there is a sea of mobile electrons which can vibrate and carry the heat energy to the other end. Water has very less free electrons available for the conduction of heat. Therefore, the option A is incorrect.The pH of liquid does not affect the heat transfer. Therefore, the option B and D are incorrect.

So, the only correct answer is option C.

Note: In the water, most of the heat gained by the water is carried out by the convection process. Generally, the ability of conduction of heat increases from gases to liquids and then to solids. In gases, the molecules of air are situated far apart and therefore, gases do not conduct heat. In liquids, the molecule as a whole conducts heat and we don’t need to specify that the electrons carry the heat energy.