Corrosion and Its Prevention

Q.

Galvanisation is a process used to prevent the rusting of which of the following?

1. Iron

2. Zinc

3. Aluminium

4. Copper

Q.

Name a silvery-grey metal.

Q. Corrosion is a gradual degradation of metals.

1. True
2. False

Q.

What is an alloy which is a major for preventing rusting of iron?

Q.

1)State and explain in brief different methods to prevent rusting of iron

2)What is displacement reaction give an example

Q. Which of the following are true in the case of corrosion?

1. Causes metals to shrink
2. Damages things made up of metals
3. Increases strength of metals
4. Metal strength remains unaffected

Q.

29. State whether the following statement is true or false.

“Chrome-plating helps in the prevention of rusting of iron.”

1. True
2. False

Q. Coating the surface of iron with other metal prevents it from rusting. If it is coated with a thin layer of zinc, it is called____________.

1. galvanization
2. painting
3. cathodic protection
   
4. None of the above

Q. How is an iron gate prevented from rusting? (2 marks)
[APSCERT Textbook]

Q. Iron articles galvanized. What is the primary reason?

1. To improve malleabilty of iron
2. To improve hardness of iron
3. It is a fancy thing to galvanize iron articles
4. To prevent rusting of iron

Q.

Why is the rusting of iron termed as a chemical change?

1. It can be cleaned and the original substance can be recovered.

2. A new substance is formed.

3. It is a temporary change.

4. It is a slow reaction.

Q. Suggest some ways to prevent rusting of iron objects

Q.

Why is the rusting of iron termed as a chemical change?

1. A new substance is formed.

2. It is a temporary change.

3. It can be cleaned and the original substance can be recovered.

4. It is a slow reaction.

Q. Name the following:
The process of coating of iron with zinc.

Q. Give an example each of a change that involves:
(a) A change in colour
(b) Evolution of a gas
(c) Production of sound

Q. Iron is galvanized by coating it with:

1. nickel
2. copper
3. chromium
4. zinc

Q. I have two doubts please answer them

Q. When objected are galvanized which of the following metal is used to protect iron?

1. zinc
2. gold
3. silver
4. copper

Q. Iron articles are shiny when new, but get coated with a reddish brown layer when left in open for a long time.

1. True
2. False

Q.

Differentiate between: Electroplating and galvanization.

Q. A shiny brown metal X when exposed to the atmosphere undergoes corrosion and develops a greenish layer Y on its surface. Identify X and Y.

1. X: Copper
   Y: Copper sulphate
2. X: Copper
   Y: Copper carbonate
3. X: Iron
   Y: Iron oxide
4. X: Iron
   Y: Iron hydroxide

Q. Which of the following metals do not undergo corrosion?

1. Iron
2. Gold
3. Copper
4. Silver

Q. Statement I: If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust.

Statement II: Rusting of iron is a chemical change.

1. Both the statements are correct.
2. Both the statement are incorrect.
3. Only statement I is correct.
4. Only statement II is correct.

Q. During corrosion, iron reacts with which of the following substances that are present in the atmosphere?

1. Oxygen
2. Moisture
3. Nitrogen
4. Carbon dioxide

Q. The process of depositing a layer of any desired metal on another material by means of electricity is called :

1. Galvanizing
2. Buffing
3. Polishing
4. Electroplating

Q. Galvanising is the process of coating iron with layer of molten:

1. Silver
2. Copper
3. nickel
4. zinc

Q. Galvanization is the:

1. deposition of aluminium on iron
2. deposition of copper on iron
3. deposition of tin on iron
4. deposition of zinc on iron

Q. Statement I: Corrosion occurs when metals are exposed to atmospheric oxygen and water.
Statement II: Galvanisation is the process of applying thin zinc coating over iron articles.

1. Only statement I is correct
2. Only statement II is correct
3. Both statements are incorrect
4. Both statements are correct

Q. Iron when reacts with moist air forms a reddish brown layer of iron oxide which is known as rust.

1. True
2. False

Q. Which of the following metal is used to coat iron articles during galvanisation?

1. Lead
2. Mercury
3. Zinc
4. Copper