Electrodes and Electrolyte

Q.

Why is a DC used in electrolysis?

Q.

If an electric current is passed through the electrodes that are immersed in water, then bubbles of oxygen and hydrogen are produced. Identify the correct statement from the following.

1. No gas bubbles are formed.

2. Oxygen bubbles formed on the electrode connected to the positive terminal of the battery

3. Hydrogen bubbles formed on the electrode connected to the positive terminal of the battery

4. Both Oxygen and Hydrogen bubbles are formed on the electrode connected to the positive terminal of the battery.

Q.

Name the electrolyte used for electroplating an article with silver?

Q.

When electrodes are immersed in water and electricity is passed, in which electrode hydrogen and oxygen bubbles arises?
[2 MARKS]

Q.

Electrolytes conduct electricity due to the movement of :
(a) electrodes
(b) atoms
(c) electrons
(d) ions

Q.

Explain why: In the electroplating of an article with silver, the electrolyte sodium argentocyanide solution is preferred over silver nitrate solution.

Q.

Differentiate between the lactometer and acid battery hydrometer.

Q.

Suggest A List Of Metals That Are Extracted Electrolytically

Q. We get some items made from iron wire in which iron wire is coated with plastic. Is plastic coated by the process of electroplating? Why can't plastic be coated on a metal by the process of electroplating?

Q. What is a voltalic cell?

Q.

What happens when electrodes are immersed in water and a current is passed? Which electrode will wear out faster and why? [3 MARKS]

Q.

What voltage is best for electrolysis?

Q. How many types of electrochemical cells are there ? Is electrolytic cell is also an electrochemical cell ?

Q.

An arrangement having two carbon rods kept in a conducting liquid in a vessel is known as :
(a) rechargeable cell
(b) storage cell
(c) biological cell
(d) electrolytic cell

Q. Rahul wants to electroplate a silver plate with zinc. He uses an arrangement as shown in the figure. Select the correct combination of electrodes and electrolyte.

1. 1: Zinc plate, 2: Silver plate, 3: Silver sulphate solution
2. 1: Zinc plate, 2: Silver plate, 3: Zinc sulphate solution
3. 1: Zinc plate, 2: Silver plate, 3: Copper sulphate solution
4. 1: Silver plate, 2: Zinc plate, 3: Silver sulphate solution

Q. Which of the following is not a requirement for fine coating in the process of electroplating?

1. The object to be electroplated should be free from greasy matter.
2. The surface of the article should be smooth so that the metal deposited sticks permanently.
3. The concentration of the electrolyte should be adjusted so as to get a smooth coating.
4. Current must be the same throughout.

Q.

When water is electrolyzed, it should preferably be free of all impurities.

1. True
2. False

Q. The electrolyte that can be used in the process of copper plating is .

1. copper sulphate
2. sodium chloride
3. copper carbonate
4. lead carbonate

Q.

If an electric current is passed through the electrodes that are immersed in water, then bubbles of oxygen and hydrogen are produced. Identify the correct statement from the following.

1. Oxygen bubbles formed on the electrode connected to the positive terminal of the battery

2. Hydrogen bubbles formed on the electrode connected to the positive terminal of the battery

3. Both Oxygen and Hydrogen bubbles are formed on the electrode connected to the positive terminal of the battery.

4. No gas bubbles are formed.

Q.

If an electric current is passed through the electrodes that are immersed in water, then bubbles of oxygen and hydrogen are produced. Identify the correct statement from the following.

1. Oxygen bubbles formed on the electrode connected to the positive terminal of the battery

2. Hydrogen bubbles formed on the electrode connected to the positive terminal of the battery

3. Both Oxygen and Hydrogen bubbles are formed on the electrode connected to the positive terminal of the battery.

4. No gas bubbles are formed.

Q. Show dissociation and ionization of :
1. Hydrochloric acid
2. Sodium hydroxide
3. Sulphuric acid
4. Acetic acid

Q.

During the electroplating of silver, silver nitrate is not used as electrolyte. Explain?

Q. The passage of an electric current through a solution causes ______________ effects.

1. electric
2. chemical
3. gravitational
4. magnetic

Q. Observe the following figure and identify electrolyte Z.

1. Silver nitrate
2. Zinc sulphate
3. Copper sulphate
4. Potassium sulphate

Q. A greenish-blue spot appears around the wire connected to the terminal of the battery while testing the potato.

1. positive
2. negative
3. neutral

Q.

Explain the electrolysis of water.

Q. The chemical reaction in an electrolytic solution, due to passage of electric current, depends on:

1. Electrodes
2. All of these
3. Magnitude of current
4. Density of liquid

Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> When two copper wires are planted in a potato and connected to a battery, why greenish blue spot is found only around the wire connected to the positive terminal?

1. Copper gets electroplated.
2. Copper reacts with air.
3. Potato gets rotten by the heat.
4. Starch reacts with air.

Q. An electrode is made of a substance which is a bad conductor of electricity.

1. False
2. True

Q. The process of chemical decomposition produced by passing an electric current through a liquid is known as:

1. Electrolysis
2. Electroplating
3. Electrochemistry
4. Galvanization