Corrosion

Q.

Can you please provide me with all important questions of chemical reactions and equations

Q. In electrolysis of water, why is the volume of gas collected over one electrode double the volume of gas collected over the other electrode?

1. Because cathode is stronger than anode
2. Because oxygen is twice as hydrogen
3. Because oxygen is more electronegative.
4. Because hydrogen is twice as oxygen

Q.

What is chemical formula of rust?

Q.

Solve: Iron$\left(\mathrm{Fe}\right)+$ oxygen$\left({\mathrm{O}}_2\right)+$water$\left({\mathrm{H}}_2\mathrm{O}\right)=?$

Q.

What is the chemical formula for corrosion in copper and silver?

Q.

How would you balance ${\mathrm{PCl}}_5+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{H}}_3{\mathrm{PO}}_4+\mathrm{HCl}$

Q.

When a strip of Zinc is added to a Copper sulphate solution, the colour changes to?

1. Red

2. Green

3. No colour change

4. Colourless

Q.

A silver article turns black when kept in the open for a few days due to the formation of :

1. ${\mathrm{H}}_2\mathrm{S}$

2. $\mathrm{AgS}$

3. ${\mathrm{AgSO}}_4$

4. ${\mathrm{Ag}}_2\mathrm{S}$

Q.

What is corrosion? Explain its advantages and disadvantages.

Q.

Aluminium is a reactive metal but still it is used for packing food articles. Give reason.

Q.

What is corrosion give two examples?

Q. What happens when iron nail is left exposed to humid air?

Q.

The black coating on Silver is due to_______?

Q. Question 13
Silver articles become black on prolonged exposure to air. This is due to the formation of:
(a) ${\text{Ag}}_3\text{N}$
(b) ${\text{Ag}}_2\text{O}$
(c) ${\text{Ag}}_2\text{S}$
(d) ${\text{Ag}}_2\text{S}$ and ${\text{Ag}}_3\text{N}$

Q.

Write harmful effects of corrosion.

Q.

Chemically rust is:

1. Hydrated ferrous oxide

2. Hydrated ferric oxide

3. Only ferric oxide

4. None of these

Q.

What is meant by rusting of iron? With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.

Q. What is formula of Cement

Q.

Give Reasons: Copper And Brass Utensils Should Be Tinned.

Q.

When iron (Fe) is exposed to moist atmosphere for a long time, rust is formed which is a layer of a brown flaky substance. What is the chemical composition of this iron rust?

1. Iron oxide
2. Hydrated Iron oxide
3. Iron
4. Moisture and Oxygen

Q.

The formation of rust when the Iron is exposed to moist air is called ________.

Q. Differentiate between rusting and burning?

Q.

A copper article if exposed to air, develops a green coloured layer of:

1. copper carbonate

2. copper oxide

3. copper sulphate

4. copper sulphide

Q.

(a) Explain the term "corrosion" with an example. Write a chemical equation to show the process of corrosion of iron.

(b) What special name is given to the corrosion of iron ?

(c) What type of chemical reaction is involved in the corrosion of iron ?

(d) Name any three objects (or structures) Which are gradually damaged by teh corrosion of iron and steel.

Q.

Which metal becomes black in the presence of hydrogen sulphide gas in air?

Q. Question 20.1

Explain the following term with one example: Corrosion.

Q.

Can rusting of iron takes place in distilled water ?

Q.

Silver metal does not combine easily with oxygen but silver jewellery transishes after some time. How?

Q. Alloying is a very good method of improving the properties of a metal. Alloys are mixtures of metals with ___.

1. either A or B can be used
2. Neither A nor B can be used
3. Non-metals
4. Metals

Q.

Why Is Iron Corrosion Such A Serious Issue?