Science Question Answer (2 Marks)

The chromium metal is suitable for electroplating it on car bumpers, bath taps and bicycle handlebars, etc., made of iron because it is corrosion resistant and also gives shiny appearance.

Sea water is a better conductor because it contains sodium and chloride ions in large amounts. These ions make the solution conducting and thus, sea water is considered better conductor than the tap water which does not contain ions in large amounts.

Electroplating is the process in which a coating of one metal can be deposited on the surface of another metal by using current from a battery. The metal that needs to be deposited is used as the cathode while the metal on which it is deposited is used as anode. We use the salt of the cathode as the electrolyte.

The two most common examples of the chemical effect of electric current are:

1. Gold Coating on cheap metals.
2. Electroplating of chromium metal to avoid corrosion.

Lemon juice, Milk, Vinegar, common salt solution, Sulphuric acid solution, Sea water, and Rainwater conduct electricity.
Sugar solution, Distilled water and Honey do not conduct electricity.

1. Heating effect of current is used detecting the flow of current through a solution.
2. Magnetic effect of current is used detecting the flow of current through a solution.

Rain water can collect salts from the atmosphere has some dissolved salts whereas the distilled water does not. Thus, the rainwater showed the deflection because it conducts electricity.

No. Pure water does not conduct electricity. Pure water does not contain any ions which make it conducting. But it can conduct electricity when a pinch of common salt is added to it, as salt solution is conducting in nature.

1. Oxygen Gas is produced at positive carbon electrode.
2. Hydrogen gas is produced as negative carbon electrode.

1. Chromium is electroplated on other metals.
2. Gold is electroplated on other cheap metals.

1. Chromium plating is done on metals body parts of cars, bikes, cycles, etc.
2. Gold and silver plating is done on the artificial jewelry.

Distilled water does not conduct electricity because it does not contain any ions which make it conducting. But it can conduct electricity when a pinch of common salt is added to it, as salt solution is conducting in nature.

When electric current passes through a conducting liquid, it gets decomposed into ions.
The conducting solution has free ions available which conduct electricity.

The electric bulb glows because it completes the circuit when put in the conducting solution and the conducting solution helps to glow the bulb.

Lemon solution, salt, vinegar, sulphuric acid etc. can be added to added to distilled .water in small amounts to make it a good conductor of electricity. Because distilled water does not contain any ions which make it conducting. But adding these will provide free ions for conducting solution.

Lemon juice is a good conductor of electricity. Lemon is a citrus fruit containing citric acid. Acids give H+ ions when dissolved in water, these free cations and anions make lemon juice a good conductor.