Selina solutions for Concise Chemistry [English] Class 8 ICSE chapter 9 - Carbon and Its Compounds [Latest edition]

Fill in the blank

 ................. is present in both living and non-living things.

Fill in the blank.

The tendency of an element to exist in two or more forms but in the same physical state is called ................

______ and ______ are the two major crystalline allotropes of carbon.

Fill in the blank.

............. is the hardest substance that occurs naturally.

Fill in the blank.

The name ‘carbon’ is derived from the Latin word...........

Choose the correct alternative.

In combined state, carbon occurs as

Choose the correct alternative.

 A crystalline form of carbon is

Choose the correct alternative.

Graphite is not found in

Choose the correct alternative.

Diamond is used for

Choose the correct alternative.

Carbon forms innumerable compounds because

Write true or false

Carbon constitues 0.03% of the earth’s crust.

Write true or false

Graphite is the purest form of carbon.

Write true or false

Coloured diamonds are costlier than colourless and transparent diamonds

Write true or false

Graphite has layers of hexagonal carbon bondings. 

Write true or false

Diamond is insoluble in all solvents. 

Define the Following Term: Allotropy

Define the Following Term :

Carat

Define the Following Term:

Crystal

Define the Following Term:

Catenation

State the term:

Substances whose atoms or molecules are arranged in a definite pattern. 

State the term:

Different forms of an element found in the same physical state. 

State the term:

The property by which atoms of an element link together to form long chain or ring compounds. 

Name the following:

The hardest naturally occurring substance.

Name the following:

A greyish black non- metal that is a good conductor of electricity. 

Name the following:

The third crystalline form of carbon. 

Answer the following question

Why is graphite a good conductor of electricity but not diamond?

Answer the following question

Why is diamond very hard?

Answer the following question

What are fullerenes? Name the most common fullerenes.

Answer the following question

What impurity is present in black diamond?

Answer the following question

Explain the softness of graphite with reference to its structure.

Give two uses of graphite.

Give two uses of diamond.

Write three differences between graphite and diamond. 

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.............is formed when charcoal is burnt in a limited supply of air.

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Coal is a ............. form of carbon.

Fill in the blank:

......... is the most inferior form of coal.

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Wood charcoal is a..........conductor of heat and electricity.

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...............is used in making black shoe polish.

Choose the correct alternative

Anthracite is

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Destructive distillation of coal yields

Choose the correct alternative

Lamp black is

Choose the correct alternative

The process by which decayed plants slowly convert into coal is called.

Choose the correct alternative

The purest form of the amorphous carbon is

Write ‘True’ Or ‘False’ Against the Following Statement: 

Charcoal is a good adsorbent.

Write ‘true’ or ‘false’ against the following statement:

Coke is obtained by destructive distillation of sugar.

Write ‘true’ or ‘false’ against the following statement:

Activated charcoal is a good conductor of electricity. 

Write ‘true’ or ‘false’ against the following statement:

Wood charcoal is an important constituent of gun powder.

Write ‘true’ or ‘false’ against the following statement:

Coal gas is used in the preparation of artificial ferilizers. 

Define the following:

Carbonization

Define the following:

Adsorption

Define the following:

Bone black

Name the following:

Substances whose atoms or molecules are not arranged in a geometrical pattern. 

Name the following:

The best variety of coal.

Name the following:

The purest form of amorphous carbon.

Name the following:

An amorphous form of carbon that contains about 98% carbon. 

Name the following:

 Mixture of carbon monoxide and hydrogen. 

What is destructive distillation? What are the products formed due to the destructive distillation of coal?

 Why is wood charcoal used in water filters and gas masks?

How is wood charcoal made locally? What other substances are formed in the process.

How many carbon atoms are there in Buckminster fullerenes?

Descirbe the formation of coal

Name four types of coal with percentage of carbon present in each,with uses.

Name the products formed when:

wood is burnt in the absence of air.

Name the products formed when:

bone is heated in the absence of air.

Name the products formed when:
 diamond is burnt in air at 900°C.

Name the products formed when:

 graphite is subjected to high pressure and 3000°C temperature.

What are the uses of coal?

Give two uses for  the following:

coke

Give two uses for  the following:

wood charcoal

Give two uses for the following:

sugar charcoal

Give two uses for the following:

bone charcoal

Give two uses for the following:

lampblack

Name the chemicals required for the preparation of carbon dioxide in the laboratory.

 How will you collect the gas ?

Write the balanced chemical equation for the above reaction.

Draw a labelled diagram for the preparation of CO₂ in the laboratory.

Why is sulphuric acid not used for the preparation of carbon dioxide in the laboratory 

Write the balanced chemical equation for the preparation of carbon dioxide by:

heating calcium carbonate.

Write the balanced chemical equations for the preparation of carbon dioxide by: 

the action of acetic acid on sodium bicarbonate.

Write the balanced chemical equations for the preparation of carbon dioxide by:

the action of dilute sulphuric acid on sodium bicarbonate.

What happens when a lit splinter is introduced into a jar containing carbon dioxide ?

What happens when moist blue litmus paper is placed in a jar containing carbon dioxide?

What happens when carbon dioxide is passed through lime water first in small amounts and then in excess ?

What happens when a baking mixture containing baking powder is heated?

What happens when a soda water bottle is opened ?

Give a reason for the following:

An excess of carbon dioxide increases the temperature of the earth.

Give reason for the following:

Soda acid and foam types of fire extinguisher are not used for extinguishing electrical fires.

Give reason for the following:

Solid carbon dioxide is used for refrigeration of food.

What is a fire extinguisher ? What is the substance used in the modern type of fire extinguishers ? How is it an improvement over the soda acid-type and the foam-type fire extinguishers ?

Explain the term ‘green house effect’. How can it be both beneficial and harmful for life on earth ?

What steps should be taken to balance carbon dioxide in the atmosphere ?

State three ways by which carbon dioxide gas is added into the atmosphere.

Fill in the blank

....................... is formed when carbon is burnt in a limited supply of air or oxygen.

Carbon monoxide burns in air with a ______ flame to form carbon dioxide.

Fill in the blank:

Carbon monoxide is a products of..................combustion.

Fill in the blank:

 A mixture of 95% oxygen and 5% carbon dioxide is called .................

Fill in the blank:

carbon dioxide is used as a..................... in the extraction of pure metals from their corresponding ores.

Match the colunm 

How is carbon monoxide gas formed?

State the poisonous nature of carbon monoxide?

Give two uses of carbon monoxide.

Why is carbon monoxide called silent killer ?

Explain the reducing action of carbon monoxide.

Write two remedies for carbon monoxide poisoning.

Complete the reactions and balance them.
CuO + CO →

Complete the reaction and balance them.

Fe₂O₂ + CO →