Conduction of Electricity in Water

Q. In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area. Explain why they do this?

Q.

A sugar solution is a better conductor of electricity when compared to a salt solution.

1. False

2. True

Q.

What makes tap water a fairly good conductor of electricity?

1. None of these

2. Its temperature

3. Dissolved salts

4. Its property of being a universal solvent

Q. We know that distilled water is a poor conductor of electricity. Which of the following can be added to distilled water to make it a good conductor?

1. Sugar
2. Oil
3. Kerosene
4. Common salt

Q. Electrodes are immersed in water and electric current is passed through it. Which of the following statements is correct?

1. Hydrogen gas will be formed at the electrode which is connected to the positive terminal of the battery

2. Hydrogen gas will be formed at the electrode which is connected to the negative terminal of the battery

3. No gas is formed at any electrode

4. Oxygen bubbles will be formed at the electrode which is connected to the negative terminal of the battery

Q.

There is a sample of water. However it is unknown if the sample is that of pure distilled water or it contains salts and other impurities. Can you determine if it will conduct electricity or not with just the given information?

1. Yes

2. Depends on temperature of water

3. Can't be said

4. No

Q.

Why is it advised to cut off power supply and switch off all electrical appliances at the time of a flood?

1. Because water is a good conductor of electricity.

2. Because water is a poor conductor of electricity.

3. Because it is important to save electricity.

4. None of these.

Q. Why don't we get electrocuted everytime we touch an electric switch but get a shock when it is wet?

1. Water has free electrons.
2. Water provides extra insulation.
3. Water increases conduction.
4. Water decreases conduction.

Q. Which of the following gases are released during electrolysis of water?

1. Chlorine and nitrogen
2. Hydrogen and oxygen
3. Oxygen and chlorine
4. Hydrogen and chlorine

Q. Distilled water is a poor conductor of electricity. On the other hand, tap water when brought into contact with an electrical conductor can cause fatal electrocution. What makes the difference?

1. Tap water has extra electrons.
2. Impurities in tap water has ions.
3. Tap water has static electricity.
4. Tap water has a conductor in it.