NCERT Exemplar Solution Class 10 Science Chapter 4
NCERT Exemplar Solution Class 10 Science Chapter 4 Carbon and its Compounds all Questions Answer Solution. NCERT Exemplar Class 10 Science Chapter 4 Solution PDF.
NCERT Exemplar Solution Class 10 Science Chapter 4: Overview
NCERT Exemplar Solution Class 10 Science Chapter 4 |
|
Board |
NCERT |
Topic |
Exemplar Problem Solution |
Class |
10 |
Subject |
Science |
Chapter |
4 |
Chapter Name |
Carbon and its Compounds |
NCERT Exemplar Solution Class 10 Science Chapter 4 Carbon and its Compounds
Multiple Choice Questions
1) Carbon Exists in the atmosphere in the form of
a) Carbon monoxide only
b) Carbon monoxide in traces and carbon dioxide
c) Carbon dioxide only
d) Coal
Answer:- b) Carbon monoxide in traces and carbon dioxide
Explanation: Carbon is present in the form of carbon monoxide also carbon dioxide in the atmosphere.
2) Which of the following statements are usually for carbon Compounds? These
I) Are good Conductors of Electricity
II) Are poor conductors of Electricity
III) Have strong forces of attraction between their molecules
IV) Do not have strong forces of attraction between their molecules
a) I and III
b) II and III
c) I and IV
d) II and IV
Answer:- d) II and IV
Explanation: Carbon Compounds are poor conductor of electricity as they are formed by the covalent bonds, hence these arealso has weak force of attraction.
3) A molecule of Ammonia (NH3) has
a) Only single bonds
b) Only double bonds
c) Only triple bonds
d) Two double bonds and one single bond
Answer:- a) Only single bonds
Explanation: Three molecules of hydrogen are connected to the one molecule of nitrogen by the three covalent bonds which are single bonded.
4) Buckminsterfullerene is an allotropic form of
a) Phosphorus
b) Sulphur
c) Carbon
d) Tin
Answer:- c) Carbon
Explanation: Buckminsterfullerene is the allotropic form of carbon, along with that carbon has many allotropes which are Graphite, diamond and amorphous carbon etc.
5) Which of the following are correct structural isomers of butane?
a) I and III
b) II and IV
c) I and II
d) III and IV
Answer:- c) I and II
Explanation: I and II structure shows the correct representation of structural isomers of Butane. Because isomers are those which have same molecular formula but different structural formula which is shown by I and II.
a) Reducing agent
b) Oxidising agent
c) Catalyst
d) Dehydrating agent
Answer:- b) Oxidising agent
Alkaline KMNO4 acts as an oxidising agent The oxidation of ethanol takes place in the reaction which results in the replacement of two Hydrogen atoms by oxygen.
7) Oils on heating with Hydrogen in the presence of palladium or nickel catalyst form fats. This is an example of
a) Addition reaction
b) Substitution reaction
c) Displacement reaction
d) Oxidation reaction
Answer:- a) Addition reaction
Explanation: The addition of Hydrogen in the oil which is unsaturated compound in the presence of catalyst undergoes the Hydrogenation reaction which results in the formation of saturated Hydrocarbons i.e. fats.
8) In which of the following compounds, -OH is the functional group?
a) Butanone
b) Butanol
c) Botanoicacid
d) Butanal
Answer:- b) Butanol
Explanation: Butanol has suffix ol which shows that the compound contains -OH functional group which represents the alcohol.
9) The soap molecule has a
a) Hydrophilic head and a hydrophobic tail
b) Hydrophobic head and a hydrophilic tail
c) Hydrophobic head and a hydrophobic tail
d) Hydrophilic head and a hydrophilic tail
Answer:- a) Hydrophilic head and a hydrophobic tail
Explanation: In the micelles hydrophobic tail is inside the spherical shaped which trapes the oil. And the outer hydrophilic head is present on the outer surface so that it could form bond with water easily. These process removes the stain easily.
10) Which of the following is the correct representation of electron dot structure of nitrogen ?
Answer:- d)
D shows the correct representation of electron dot structure of nitrogen. D has correct 8 electrons of nitrogen atoms.
11) Structural formula of ethylene is
Answer:- a)
A shows the correct representation of structural formula of ethylene.
12) Identify the unsaturated compounds from the following
I) Propane
II) Propene
III) Propyne
IV) Chloropropane
a) I and II
b) II and IV
c) III and IV
d) II and III
Answer:- d) II and III
Explanation: Propene and propyne are the unsaturated compounds because these contains double and triple bonds respectively.
13) Chlorine reacts with saturated hydrocarbons at room temperature in the
a) Absence of sunlight
b) Presence of sunlight
c) Presence of water
d) Presence of hydrochloric acid
Answer:- b) Presence of sunlight
Explanation: Here the displacement reaction occurs when Chlorine reacts with saturated hydrocarbons in the presence of sunlight, these is also known as substitution reaction which replace the H atom by cl.
14) In the soap micelles
a) The ionic end of soap is on the surface of the cluster while the Carbon chain is in the interior of the cluster.
b) Ionic end of soap is in the interior of the cluster and the Carbon chain is out of the cluster.
c) Both ionic end and carbon chain are in the interior of the cluster.
d) Both ionic end and carbon chain are on the exterior of the cluster.
Answer:- a) The ionic end of soap is on the surface of the cluster while the Carbon chain is in the interior of the cluster.
Explanation: The spherical shaped aggregate formed in the soap solution are known as micelles. These micelles have two parts ionic ends which are present over the cluster and the another carbon chain is present inside the cluster formed, which looks like spherical shaped.
15) Pentene has the molecular formula C5H12 . It has
a) 5 covalent bonds
b) 12 covalent bonds
c) 16 Covalent bonds
d) 17 Covalent bonds
Answer:- c) 16 Covalent bonds
Explanation: C5H12 is the molecular formula of pentene which contains the 16 Covalent bonds that is sharing of electrons for the formation of bonds.
16) Structural formula of benzene is
Answer:- c)
C shows the correct structural formula of benzene.
17) Ethanol reacts with sodium and forms two products.
a) Sodium ethanoate and hydrogen
b) Sodium ethanoate and oxygen
c) Sodium ethoxide and hydrogen
d) Sodium ethoxide and oxygen
Answer:- c) Sodium ethoxide and hydrogen
When Sodium and ethanol reacts they gives the product of sodium ethoxide and hydrogen.
The reaction is carried out as –
2Na + 2CH3CH2OH → 2CH3CH2ONa + H2
18) The correct structural formula of butanoic acid is
Answer:- d)
D shows the correct structural formula of butanoic acid.
19) Vinegar is a solution of
a) 50% – 60 % acetic acid in alcohol
b) 5% – 8% acetic acid in alcohol
c) 5% – 8 % acetic acid in water
d) 50 % – 60 % acetic acid in water
Answer:- c) 5% – 8 % acetic acid in water
Explanation: Vinegar form by the mixture of 5 to 8 % of acetic acid adding in water.
20) Mineral acids are stronger acids than carboxylic acids because
I) Mineral acids are completely ionised
II) Carboxylic acids are completely ionised
III) Mineral acids are partially ionised
IV) Carboxylic acids are partially ionised
a) I and IV
b) II and III
c) I and II
d) III and IV
Answer:- a) I and IV
Explanation: Mineral acids are stronger than the carboxylic acid because these are formed by Ionisation process.
21) Carbon forms four covalent bonds by sharing it’s four bonds, Carbon attains the electronic configuration of
a) Helium
b) Neon
c) Argon
d) Krypton
Answer:- b) Neon
Explanation: When carbon forms 4 bonds Covalently with another univalent atom, the electronic configuration of carbon shows same E.C as Neon.
22) The correct electron dot structure of water molecule is
Answer:- c)
C shows the correct electron dot structure of water molecule.
23) Which of the following is not a straight chain hydrocarbons ?
Answer:- d)
D is not a straight chain hydrocarbons, it has two CH3 group attached to single hydrogen, that is it is branched.
24) Which among the following are unsaturated hydrocarbons ?
a) I and III
b) II and III
c) II and IV
d) III and IV
Answer:- c) II and IV
Explanation: These compounds contains the double and triple bonds hence these are unsaturated.
25) Which of the following does not belong to the same homologous series?
A) CH4
B) C2H6
C) C3H8
D) C3H8
Answer:- D) C3H8
Explanation: The other given options belongs to the same homologous series which have the general formula CnH2n+1
But C3H8 belongs to CnH2n.
26) The name of the compound CH3- CH2 – CHO is
a) Propanal
b) Propanone
c) Ethanol
d) Ethanal
Answer:- a) propanal
Explanation: The given compound contains aldehyde group hence al suffix should be there, and the compound contains 3 carbon atoms hence propanal.
27) The heteroatoms present in
CH3-CH2-O-CH2-CH2Cl are
I) Oxygen
II) Carbon
III) Hydrogen
IV) Chlorine
a) I and II
b) II and III
c) III and IV
d) I and IV
Answer:- d) I and IV
Explanation: The heteroatoms present in the equation is Oxygen and Chlorine. Hydrocarbons are the compounds made up of Hydrogen and Carbon beside that all the other atoms are heteroatoms.
28) Which of the following represents saponification reaction ?
Answer:- d)
The saponification is the process of formation of soap. Which includes the reaction of Easter with alkali to give the product of ethanol and Sodium Ethanoate.
29) The first member of alkyne homologous series is
a) Ethyne
b) Ethene
c) Propyne
d) Methane
Answer:- a) Ethyne
The first member of alkyne homologous series is Ethyne. Ethyne contains 2 Carbon atoms jointed with triple bond.
Short Answer Questions
30) Draw the electron dot structure of ethyne and also draw its structural formula.
Answer:-
The electron dot structure of ethyne is –
Also the structural formula of ethyne is
31) Write the names of following compounds
Answer:- pentanoic acid
Answer:- Butyne
Answer:- Heptanal
Answer:- pentanol
32) Identify the name the functional groups present in the following compounds
Answer:-
1) Alcohol
2) Carboxylic acid
3) Ketone
4) Alkene
33) A compound X is formed by the reaction of a carboxylic acid C2H4O2 and an alcohol in presence of a few drops of H2SO4. The alcohol on oxidation with alkaline KMnO4 followed by acidification gives the same carboxylic acid as used in this reaction. Give the names and structures of (a) carboxylic acid, (b) alcohol and (c) the Compound X. Also write the reaction.
Answer:-
a) The name for Carboxylic acid Is ethanoic acid
b) Name of the alcohol is ethanol
c) Name for X is ethyl ethanoate
34) Why detergents are better cleansing agents than soaps ? Explain.
Answer:-
Detergents are better cleansing agent than the soap because soap does not work in both hard as well as soft water but the detergent does. In hard water Detergents Does not form insoluble participants with calcium and magnesium, hence it is better than the soaps.
35) Name the functional groups present in the following Compounds
a) CH3 CO CH2 CH2CH2CH3
Answer:- the functional group present in these compound is ketone.
b) CH3 CH2 CH2 COOH
Answer:- the functional group present in these compound is Carboxylic acid.
c) CH3 CH2 CH2CH2CHO
Answer:- the functional group present in the given compound is aldehyde.
d) CH3 CH2 OH
Answer:- the functional group present in the given compound is Alcohol.
36) How is ethane prepared from ethanol? Give the reaction Involved in it.
Answer:-
The reaction involved in the process of ethane prepared from ethanol is –
In these reaction Ethanol is heated over the 443 K with hot Concentrated H2SO4 which results in the product of ethane and H2O by the process of dehydration.
37) Intake of small quantity of methanol can be lethal. Comment.
Answer:-
Methanol acts worst when it goes into body. It kills many cells when it enters the liver. In liver it converted into methanal. It has some worst effect over the optic nerve, and these can cause blindness also. Thus, the intake of small quantity of methanol can be lethal.
38) A gas is evolved when ethanol reacts with sodium. Name the gas evolved and also write the balanced chemical equation of the reaction Involved.
Answer:-
The balanced chemical reaction occurs when ethanol reacts with Sodium is –
2CH3CH2OH + 2Na →2CH3CH2 O–Na+ + H2
Here, in these reaction Hydrogen gas is evolved.
39) Ethane is formed when ethanol at 443 K is heated with excess of concentrated sulphuric acid. What is the sulphuric acid in this reaction? Write the balanced chemical equation of this reaction.
Answer:-
The balanced chemical equation for the reaction is –
In these reaction, Ethanol is treated with hot Concentrated H2SO4 (Sulphuric acid) at 443 K heat and then it is Formed theproduct after goes through dehydration which is ethene and water.
Here, Sulphuric acid works as a dehydrating agent.
40) Carbon, Group (14) element in the periodic table, is known to form compounds with many elements.
Write the example if a Compound formed with
a) Chlorine (Group 17 of periodic table)
Answer:-
Carbon form the compound with the Chlorine which is a element of group 17 the compound formed is
CCl4– Carbon tetrachloride .
b) Oxygen (Group 18 of periodic table)
Answer:- Carbon forming the compound with oxygen which is an element of group 18 is
CO2 – carbon dioxide
CO – carbon monoxide
41) In electron dot structure, the valence shell electrons are represented by crosses or dots.
a) The atomic number of Chlorine is 17. Write it’s electronic configuration.
Answer:-
The electronic configuration of Chlorine which has Atomic number is 17 is –
K – 2
L – 8
M – 7
b) Draw the electron dot structure of Chlorine molecule.
Answer:-
The electron dot structure of Chlorine molecule is as follow-
42) Catenation is the ability of an atom to form bonds with other atoms of the same element. It is exhibited by both Carbon and silicon. Compare the ability of catenation of the two elements. Give reasons.
Answer:- Si- Si are weaker as compared to the C- C. Si – Si bond is weak because it has large size hence it is less stable , while the C- C bond is strong because it has a small size. Hence The ability of catenation is more than of carbon bonds than the silicon bonds.
43) Unsaturated hydrocarbons contain multiple bonds between the two C-atoms to distinguish ethane from ethene.
Answer:-
Saturated hydrocarbons are those which are single bonded these burns with a clean and whiteflame, hence ethane burns with white flame. But the unsaturated hydrocarbons which contains multiple bonds between C and C, like ethene and ethyne burns with a yellow flame.
44) Match the reactions given in Column A with the names given in Column B
Column A | Column B |
a) CH3OH + CH3OOH → CH3COOCH3 + H2O | I) Addition reaction |
b) CH2= CH2 + H2
→ CH3 – CH3 |
II) substitution reaction |
c) CH4 + Cl2 → CH3Cl + HCl | III) Neutralisation reaction |
d) CH3COOH + NaOH → CH3COONa + H2O | IV) Esterification reaction |
Answer:-
Column A | Answer |
a) CH3OH + CH3OOH → CH3COOCH3 + H2O | iv) esterification reaction |
b) CH2= CH2 + H2
→ CH3 – CH3 |
I) Addition reaction |
c) CH4 + Cl2 → CH3Cl + HCl | II) Substitution reaction |
d) CH3COOH + NaOH → CH3COONa + H2O | III ) Neutralisation reaction |
45) Write the structural Formulae of all the isomers of hexane.
Answer:-
1) Hexane
2) 2- methyl pentane
3) 2,2- dimethyl butane
4) 2,3 – dimethyl butane
5) 3- Methyl pentane
46) What is the role of metal or reagents written on arrows in the given chemical reaction ?
A. Answer :-
In these reaction the Ni that us nickel written on arrow acts like a catalyst.
B. Answer:-
In the given reaction the Concentrated H2SO4 written on arrow acts like a catalyst.
C. Answer:-
these reaction the alkaline KMnO4 acts as Oxidising agent.
Long Answer Questions
47) A salt X is formed and a gas is evolved when ethanoic acid reacts with sodium hydrogen carbonate. Name the salt X and the gas evolved. Describe an activity and drew the diagram of the apparatus to prove that the evolved gas is the one which you have named. Also, write chemical equation of the reaction involved.
Answer:-
When the reaction occurs between the ethanoic acid And Sodium Hydrogen Carbonate then there is production of Sodium Ethanoate which is the salt formed in the reaction (X) and the CO2 gas is released.
The equation for the reaction occurs is –
CH3COOH+NaHCO3 → CH3COONa + H2O + CO2
The activity which shows the Evolved gas is CO2 is passing the CO2 gas through the lime water if the lime water turns milky then it confirms the CO2 gas evolved.
These activity can be performed step by step as –
- figure shows the set up of the activity.
- the reaction is carried out in the test tube the brisk effervescence occurs in test tube.
- These brisk effervescence are CO2 gas which we have to pass from lime water.
- If the lime water turns milky as shown in figure then it confirms the CO2 gas.
The diagram shows the apparatus used in these activity.
48) a) What are hydrocarbons ? Give examples.
Answer:- the compound made up of Hydrogenand Carbon are known as Hydrocarbons.
Ex. Ethane, methane, propane, Butane, pentane, ethyne, methyne, propene, butene. Etc.
Methane Ethane ethaneethyne
Saturated unsaturated
B) Give the structural differences between saturated and unsaturated hydrocarbons with two examples each.
Answer:-
Saturated Hydrocarbons →
Saturated Hydrocarbons contains only single bond between C- C . Ex. Ethane, Methane, propane and Butane etc.
Unsaturated hydrocarbons →
Unsaturated hydrocarbons contains multiple bonds i.e. double or triple bonds between Carbon – carbon .
Ex. Ethene , ethyne , methene, methyne. Etc.
C) what is a functional group? Give examples of four different functional groups.
Answer:-
Functional groups gives the characteristics of chemical properties of the compound it is found as the set of atom in specific type joined to the compound in particular pattern.
Ex. Ketone – – C=O –
Carboxylic acid group – COOH
Aldehyde – CHO
Hydroxyl group – OH
49) Name the reaction which is commonly used in the conversion of vegetables oils to fats. Explain the reaction involved in detail.
Answer:-
The reaction which is commonly used in the conversion of vegetables oils to fats is Addition reaction. Here, the reaction occurs in which the unsaturated Vegetables oil is converted into saturated fats by the process of hydrogenation. In simple language the double bonded Carbon in the oil is converted into single bonded Carbons by the process of hydrogenation. In which nickel act as a catalyst.
The reaction takes place as follows-
50) A) write the formula and draw electron dot structure of carbon tetrachloride.
Answer:- the formula of Carbon tetrachloride is CCl4 and the electron dot structure of CCl4 is –
B.) What is saponification? Write the reaction Involved in this process.
Answer:-
The method of preparation of soap is commonly called as saponification, in which the Easter reacts with base and give the product of Sodium salt of carboxylic acid and alcohol.
The reaction takes place as –
CH3COOC2H5 + NaOH → CH3COONa + C2H5OH
51) Eaters are sweet – smelling substances and are used in making perfumes. Suggest some activity and the reaction Involved for the preparation of an Easter with well labelled diagram.
Answer:-
The Activity involved in the Preparation of Easter is as follows –
- Take a test tube , Add 1 ml of Ethanol and 1 ml of Glacial acetic acid in it.
- Add some drops of H2SO4 (sulphuric acid)
- Now, heat the test tube for 5 minutes in the water bath.
- After heating transfer the mixture into a beaker.
- Now, if the mixture smells sweet then it confirms the Formation of Easter.
The reaction involved in these process is –
52) A Compound C ( molecular formula, C2H4O2) reacts with Na- metal to form a Compound C on treatment with an alcohol A in presence of an acid forms a sweet smelling compound S (Molecular formula, C3H6O2) on addition of NaOH to C, it also gives R and water. S on treatment with NaOH Solution gives back R and A.
Identify C, R, A, S and write down the reactions involved.
Answer:-
Here,
C is ethanoic acid
A is methanol
R is Sodium acetate (Sodium salt of ethanoic acid
S is Methyl acetate (Ester )
The equation of the reactions involved in these are –
53) Look at figure 4.1 and Answer the following questions
A) What change would you observe in the Calcium hydroxide solution taken in tube B?
Answer:-
The change observed In the calcium hydroxide solution taken in test tube B is the solution turns milky, due to passing the CO2 gas in it.
B) Write the reaction involved in test tube A and B respectively.
Answer:- The reaction occurs in test tube A is –
CH3COOH+NaHCO3 → CH3COONa + CO2 + H2O
And, the reaction involved in test tube B
Ca(OH)2 + CO2 → CaCO3 + H2O
C) If ethanol is given instead of ethanoic acid, would you expect the same change?
Answer:-
No. Same result will not obtained if the Ethanol is replaced with Ethanoic acid. Because ethanol cannot react with Sodium Hydrogen Carbonate.
C2H5OH + Na2CO3 → No any change
D) How can a solution of lime water be prepared in the laboratory ?
Answer:-
The solution of lime water can be prepared in the laboratory As –
Take distilled water in a beaker, add some Calcium Carbonate powder in it. Mix them thoroughly . After some time the residue will settle down the beaker, and clear water above. Decant the above clear solution which is the lime water.
55) How would you bring about the following conversations ? Name the process and write the reaction Involved.
a) Ethanol to ethane
Answer:-
The formation of ethane from the Ethanol takes place when the Solution of ethanol is heated upon the 443 K with the help of Excess H2SO4 Sulphuric acid solution.
The reaction takes place as follows –
b) Propanol to propanoic acid
Write the reactions .
Answer:- The propanoicacid is obtained when propanol is treated with Alkaline KMnO4 or Acidified K2Cr2O2 solution.
The reaction takes place as follows –
55) Draw the Possible isomers of the Compound with molecular formula C3H6O and also give their electron dot structure.
Answer:- The compound which have same molecular formula but different structural formula are known as Isomers of each other.
The Compound with molecular formula C3H6O are propanal and propanone, these are isomers of each other.
The structural formula of The compound propanone is –
Dot structure formula of propanone compound is –
The structural formula of The compound propanal is –
The electron dot structure of the propanal is –
56) Explain the given reactions with the examples.
a) Hydrogenation Reaction
Answer:- The Reaction in which Unsaturated Hydrocarbons is converted into saturated Hydrocarbons by the addition of hydrogen is known as Hydrogenation.
It is used in the converting the vegetables oil into saturated fats.
The reaction takes place as follows –
b) Oxidation reaction
Answer:- Oxidation is the process in which a molecule of Oxygen is added to alcohol and gives the product of carboxylic acid.
The reaction of the example is –
C) Substitution reaction
Answer:- The reaction in which one molecule of hydrogen is replaced by another molecules in the presence of sunlight or Chlorine molecule.
The reaction takes place as follows –
D) Saponification reaction
Answer:-
Saponification reaction is the reaction involved in the formation of soap which takes place when Easter is treated with alkali, the product obtained of ethanol and Sodium Ethanoate.
The equation for the reaction is as follows –
CH3COOC2H5 + NaOH → CH3COONa + C2H5OH
E) Combustion reaction
Answer :- The burning of the substances in the presence of oxygen is known as combustion.
The reaction takes place as follows –
CH4 + 2O2 → CO2 + 2H2O + heat + light
57) An Organic Compound A on heating with concentrated H2SO4 forms a Compound B which on addition of one mole of Compound C on combustion forms two moles of CO2 and 3 moles of H2O. Identify the Compounds A, B and C write the chemical equations of the reaction Involved.
Answer:-
Here,
Compound A is Ethanol (CH3CH2OH)
On heating Ethanol with H2SO4 solution we get Compound B ,
The reaction is,
Hence,
Compound B is Ethene.
When hydrogenation reaction occurs over the compound B with the presence of Nickel it gives –
Thus, compound C is Ethane ( CH3- CH3 )
Now, on combustion of ethane gives the following reaction –
2C2H6 + 7O2 → 4CO2 + 6H2O