Chp 4 Carbon And Its Compounds

Question 1

Name of few things around which are made up of carbon

Answer 1

Almost everything around us has carbon. DNA is made up of amino acids which contain carbon. Carbon is also present.

Question 2

True or false- The amount of carbon present in earth’s crust and atmosphere is abundant

Answer 2

FalSe. The earth’s crust has only 0.02Percent carbon in the form of minerals( Carbonate, hydrogen carbonate, coal and petroleum). And the atmosphere has 0.03 percentage of carbon dioxide

Question 3

What are the characteristics of carbon compounds

Answer 3

• Electricity poor conductor of electricity
• Low melting and boiling point
• force of attraction is weak
• Since these compounds are largely non-conductors of electricity, we can conclude the bonding in these compounds do not give rise to any irons

Question 4

How is reactivity of elements explained

Answer 4

Reactivity of elements is explained as a tendency to attain a completely filled out a shame, that is, attain noble gas configuration. Elements forming ionic compounds achieve this by either gaing or losing electrons from out of motion in the case of carbon it has four electrons in the outer most shell

Question 5

What would be the consequences if carbon gains or lose electrons

Answer 5

If carbon gains or electrons forming c^4- Anion then it would be difficult for the nucleus with six protons to hold on 10 electrons

It can also lose four electrons to form C4 plus cation then it would require a larger amount of energy to remove four electrons leaving behind only two electrons and the nucleus holding six protons

Question 6

Name the elements having single covalent bond, double covalent bond, Triple covalent bond

Answer 6

Single- hydrogen, chlorine, water, NH3
Double- oxygen
Triple- nitrogen

Question 7

Uses of methane

Answer 7

CH4 is the major component of biogas and CNG.

Question 8

True or false-

Carbon is tetravalent

Answer 8

True bcoz it has 4 valence e-

Question 9

What a covalent bonds

Answer 9

Bonds formed by sharing of electron pairs between two atoms are known as covalent bonds.They have strong bond between the molecules intermolecular forces of week and this gives rise to low melting and boiling pointd. They are generally poor conductors of electricity

Question 10

Define allotropy

Answer 10

Rupee is the property was bought you a fetch an element exist in more than one form and each firm has different physical properties but identical chemical properties. For example-02 and 03 of oxygen, diamond diamond, graphite and fullerene of carbon.

Question 11

What is the structure of diamond

Answer 11

In diamond each carbon atom is bonded to other four carbon atoms forming a rigid three-dimensional structure and tetrahedral arrangement . It is three dimensional and Rigid

Question 12

Explain the structure of graphite

Answer 12

In graphite each carbon is bonded only three neighbouring compounds in the same plane forming layers of hexagon Array.And one of these bonds is double bond and there is a balance of carbon is satisfied. They are separated by compartively larger distance with the larger distance and held together by week force is called Vanderwaal’s force

Question 13

Describe the structure of fullerenes.

Answer 13

Fullerene Is the natural aloe tube of carbon in which 60 carbon atoms and lead to stable structure it is discovered in 1985 and since it looks like a geodesic design byUS architect Buckminster fuller, it is called fullerenes. It has 20 hexagonal faces and 12 pentagonal faces.
Uses- Super conductors, semi conductor, lubricant, catalyst ,etc

Question 14

True or false- Graphite is brittle

Answer 14

False, it is smooth n slippery

Question 15

How can we synthesise artificial diamonds

Answer 15

Diamonds can be synthesised by subjecting pure carbon to very high pressure and temperature.

Question 16

Why is graphite a good conductor and not diamond

Answer 16

In diamond all the four valance electrons in the outer shell of each carbon atom are used to make bombs so there is no free electrons. However in graphite only three valance electrons are used to make bonding and one free electron and one free e- acts as ion

Question 17

Define catenation

Answer 17

Catenation is the property of self linking of carbon atoms through covalent bonds to form long straight or branched chains and rings. They can form single bond double bond and even triple bond

Question 18

What are saturated compounds are unsaturated compounds

Answer 18

The compounds of carbon, which are linked by only one single bond between the carbon atoms are called saturated compounds. They are generally not very reactive .
The compounds of carbon having double or triple bond between the carbon atom are called unsaturated compounds and are more reactive

Question 19

What are hydrogen carbon

Answer 19

Hydrocarbon are the organic compounds containing only had risen and carbon. The major source of hydrocarbons is petroleum

Question 20

True or false- Catenation in silicon is better than the catenation in carbon

Answer 20

False. Both carbon and silicon do show the property of catenation. Silicon form compounds with hydrogen which have chains up to 7 or eight atoms. However the compounds formed a very reactive aAnd less stable. On the other hand the carbon carbon bond is very strong and stable. Thus we can say that the property of catenation in carbon is stronger

Question 21

Why are the Covalent bonds between become carbon and element is exceptionally stable

Answer 21

This is because carbon small size. This enables the nucleus to hold on to the shared pairs of electrons strongly. The bonds formed by elements having bigger atoms are much weaker

Question 22

What are. Alkanes

Answer 22

Alkanes are saturated hydrocarbons containing only carbon-carbon and hydrogen-carbon single covalent bonds. The general formula is Cn H
2n+2

For example-methane where Nis equal to 1
Ethane- C2H6 (n=2)

Question 23

What are Alkenes?

Answer 23

They are unsaturated hydrocarbons containing carbon-carbon double bond. They contain two hydrogen atoms less than alkanes
General formula- CnH
2n

For example – when n is equal to 2,
C2H4 ethylene
When n =3 , C3H6- Propene
When n=4, C4H8 Butene or butylene

Question 24

What are alkynes

Answer 24

Unsaturated hydrocarbons which contain triple carbon-carbon bonds. They contain four hydrogen atoms less than corresponding alkanes

General formula- CnH
2n-2

When n=2, C2H2 - ethane or acetylene
When n=3 , C3H4 - propyne

Question 25

What are structural isomers

Answer 25

The compounds with identical molecular formula but different structures are called isomers and the phenomena is called as isomerism

Question 26

What are the types of organic compounds

Answer 26

Organic compounds are basically of two types open chain compounds and closed chain compounds. Under closed chain compounds there is a subdivision of alicyclic and aromatic.