Question

Which of the below-given options is not a conductor?

• A. Copper wire
• B. Glass
• C. Seawater
• D. Graphite

Answer 1

The correct option is B

Glass

Step 1: Explanation of the correct option

In the case of option B,

1. A conductor is a material that permits current to flow freely through it.
2. Conductor allows the free flow of electricity due to the presence of free electrons.
3. Insulators are materials that create barriers to the free flow of electricity.
4. Glass is an insulator since it does not allow electricity to pass through it due to the absence of free electrons.
5. Glass is also a supercooled liquid.

Step 2: Explanation for the incorrect options

In the case of option A,

1. Copper wire is a good conductor of electricity due to the availability of free electrons which help in the flow of electricity.
2. Copper wires are widely used for making electrical devices and in domestic wiring.

In the case of option C,

1. Sea water is a good conductor because it contains a high concentration of chloride and sodium ions.
2. This is because the sodium and chloride salts dissociate into ions, making it a good conductor. As a result, sea water is approximately a million times more conductive than fresh water.

In the case of option D,

1. Graphite is one of three carbon allotropes.
2. Graphite is an excellent electrical conductor due to its structural configuration.
3. One carbon atom is attached to three other carbon atoms in graphite, while one carbon atom is free. Because of this, graphite is a good conductor.

Hence, option B is the correct option.