Lakhmir Singh & Manjit Kaur - Chemistry

Book: Lakhmir Singh & Manjit Kaur - Chemistry

Chapter: 4. Carbon and Its Compounds

Subject: Chemistry - Class 10th

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Chapter Exercises

Very Short Answer Type Questions-Pg-220
Short Answer Type Questions-Pg-221
Long Answer Type Questions-Pg-222
Multiple Choice Questions (MCQs)-Pg-223
Questions Based on High Order Thinking Skills (HOTS)-Pg-224
Very Short Answer Type Questions-Pg-239
Short Answer Type Questions-Pg-240
Long Answer Type Questions-Pg-241
Multiple Choice Questions (MCQs)-Pg-242
Questions Based on High Order Thinking Skills (HOTS)-Pg-243
Very Short Answer Type Questions-Pg-262
Short Answer Type Questions-Pg-263
Long Answer Type Questions-Pg-265
Multiple Choice Questions (MCQs)-Pg-265
Questions Based on High Order Thinking Skills (HOTS)-Pg-266

Very Short Answer Type Questions-Pg-220

1 Name the element whose one of the allotropic forms is Buck minster fullerence.
2 What are the two properties of carbon which lead to the formation of a large number of carbon compounds?
3 State whether the following statement is true or False:

Diamond and graphite are the covalent compounds of carbon element (C).
4 Name the scientist who disproved the ‘vital force theory’ for the formation of organic compounds.
5 Name the element whose allotropic form is graphite.
6 In addition to some propane and ethane, LPG cylinders contain mainly two isomers of another alkane. Name the two isomers and write their condensed structural formulae.
7 Buckminsterfullerence is a spherical molecule in which 60 carbon atoms are arranged in interlocking hexagonal and pentagonal rings of carbon atoms.

(a) How many hexagons of carbon atoms are present in one molecule of buckministerfullerene?


(b) How many pentagons of carbon atoms are present in one molecule of buckministerfullerence ?
8 Name the black substance of pencil. Will the current flow through the electrical circuit when we use the sharpened ends of the pencil to complete the circuit?
9 How does graphite act as a lubricant?
10 Name the hardest natural substance known.
11 Which of the following molecules is called buckministerfullerene?

C90 C60 C70 C120
12 Give the name and structural formulae of an alkyl group.
13 Write the electron-dot structure for:

(i) ethane, (ii) ethane, and (iii) ethyne.
14 Give the IUPAC name of the following compound: C2H6
15 Write the structural formulae of propene.
16 Write the structural formulae of propyne.
17 write the structural formula of butane.
18 What do you call the compounds having the same molecular formula but different structural arrangement of atoms?
19 write the names of any two isomers represented by the molecular formula C5H12.
20 Write down (i) structural formula, and (ii) electron-dot formula, of any one isomer of hexane (C6H14), other than n-hexane.
21 Fill in the following blanks with suitable words:

(a) The form of carbon which is known as black leas is ……………


(b) The form if carbon which is used as a lubricant at high temperature is …………..


(c) Compounds of carbon with hydrogen alone are called………..


(d) CnH2n is the general formula of………….. hydrocarbons.


(e) Hydrocarbons having the general formula CnH2n-2 are called ……………


(f) Ethene and ethyne are example of …………….. hydrocarbons.


(g) Ethyne has …….carbon-hydrogen single bonds.


(h) Carbon compounds have usually …………….. melting points and boiling points because they are…….. in nature.


(i) The property of carbon atoms to form long chains in compounds is called ………..


(j) The general formula CnH2n for cycloalkanes is the same as that of ………..


(k) The IUPAC name of ethyne is ……..


(l) The IUPAC name of acetylene is ……

Short Answer Type Questions-Pg-221

22 What is the atomic number of carbon. Write its electronic configuration.
22 What type of chemical bonds are formed by carbon? Why?
22 Name the three allotropic forms of carbon.
23 What is the general name of all the compounds made up of carbon and hydrogen?
23 Why does carbon form compounds mainly by covalent bonding?
24 What is meant by catenation? Name two elements which exhibit the property of catenation.
24 Write the names and structural formulae of all the possible isomers of hexane.
25 What is buckminsterfullerence? How is it related to diamond and graphite?
25 Why is diamond used for making cutting tools (lie glass cutters) but graphite is not?
25 Why is graphite used for making dry cell electrodes but diamond is not?
26 Give the general formula of an: (i) alkane (ii) alkene (iii) alkyne.
26 Classify the following compounds as alkanes, alkenes, an alkynes:

C2H4, C3H4, C4H8, C5H8, C3H8, C5H12
27 (i) Friedrich Wohler converted an inorganic compound into an organic compound in the laboratory.

(ii) Write the name and formula of organic compound formed.
27 Give the molecular formula of butane and mention the names of its two isomers. Name one fuel which contains both these isomers.
28 Give IUPAC names and formulae of an organic compound containing single bonds and the other containing both a triple bond.
28 Which of the following is the molecular formula of benzene?

C6H6, C6H10, C6H12, C6H14,
28 Which of the two has a branches chain: isobutene or normal butane?
29 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.
30 how can diamonds be made artificially? How do synthetic diamonds differ from natural ones?
30 Give any two differences between the properties of diamond and graphite. What causes these differences?
31 Why does the element carbon form a large number of carbon compounds?
31 Write down the structure and name of two isomers of butane (C4H10).
32 Give the name and structure formula of one member each of the following:

(i) alkane


(ii) alkene


(iii) alkyne


(iv) cycloalkane
32 Give the common name of (i) ethyne, and (ii) ethane.
32 Write the molecular formula and structure of benzene.
33 What is the unique property of carbon atom? How is the property helpful to us?
33 Explain why, diamond is hard while graphite is soft (though both are made of carbon atoms).
34 Giving their structures, state the number of single bonds and triple bonds (if any) in the following compounds:

(i) ethyne


(ii) ethane


(iii) benzene
34 Write the molecular formula and structure of cyclohexane. How many covalent bonds are there in a molecular of cyclohexane?
35 Write the points of different in the structure of diamond and graphite.
35 Explain why, graphite can be used as a lubricant but diamond and graphite.
35 Explain why, diamond can be used in rock drilling equipment but graphite cannot.
35 State one use of diamond which depend on its ‘extraordinary brilliance’ and use of graphite which depends on its being ‘black and quite soft.’

Long Answer Type Questions-Pg-222

36 What is diamond? Of what substance is diamond made?
36 Describe the structure of diamond.
36 Explain why, diamond has a high melting point.
36 State any two uses of diamond.
37 What is graphite? Of what substance is graphite made?
37 Describe the structure of graphite with the help of a labeled diagram.
37 Why is graphite a good conductor of electricity but diamond is a non- conductor of electricity?
37 State any two uses of graphite.
38 Explain the term ‘isomers’. Give one example of isomers.
38 Write (i) structural formula, and (ii) electron-dot structure, of any one isomer of n-heptane (C7H16).
38 Write IUPAC name of the compound having the formula n-C4H10.
38 Give the IUPAC names for the following:
39 What are hydrocarbons? Explain with examples.
39 Explain the meaning of saturated and unsaturated hydrocarbons with two examples each.
39 Give the names and structure formulae of one saturated cyclic hydrocarbon and one unsaturated hydrocarbon.
39 Give one example of a hydrocarbon, other than pentane, having more than three isomers.
39 How many isomers of the following hydrocarbons are possible?

(i) C3H8,


(ii) C4H10,


(iii) C5H12,


(iv) C6H14,

Multiple Choice Questions (MCQs)-Pg-223

40 Buckministerfullerence is an allotropic form of the element:
41 Out of the following pairs of compounds, the unsaturated compounds are:
42 The number of covalent bonds in pentane (molecular formula C5H12) is
43 The property of self- combination of the same element to form long chains is known as:
44 A cyclic hydrocarbon having carbon-carbon single bonds as well as carbon-carbon double bonds in its molecule is:
45 The hydrocarbon 2-methylbutane is an isomer of:
46 An unsaturated hydrocarbon having a triple covalent bond has 50 hydrogen atoms in its molecule will be:
47 An alkyne has seventy-five carbon atoms in its molecule. The number of hydrogen atoms in its molecule will be:
48 A diamond-toothed saw is usually used for cutting:
49 The organic compound prepared by Wohler from an inorganic compound called ammonium cyanate was:
50 One of the following is not an allotrope of carbon. This is:
51 The number of carbon atoms in the organic compound named as 2, 2-dimethylpropane is:
52 The pair of elements which exhibits the property of catenation is:
53 A saturated hydrocarbon has fifty hydrogen atoms in its molecule. The number of carbon atoms in its molecule will be:
54 A hydrocarbon having one double bond has 100 carbon atoms in its molecule. The number of hydrogen atoms in its molecule will be:
55 The hydrocarbon which has alternate single and double bonds arranged in the form of a ring is:
56 Which of the following cannot exhibit isomerism?
57 The pencil leads are made of mainly:
58 The number of isomers formed by the hydrocarbon with molecular formula C5H12 is:
59 The number of carbon atoms joined in a spherical molecule of buckministerfullerence is:

Questions Based on High Order Thinking Skills (HOTS)-Pg-224

60 A solid element X has four electrons in the outermost shell of its atom. An allotrope Y of this element is used as a dry lubricant in machinery and also in making pencil leads.

(a) What is element X?


(b) Name the allotrope Y?


(c) State whether allotrope Y is a good conductor or non-conductor of electricity.


(d) Name one use of allotrope Y (other than lubrication and pencil leads)


(e) Name two other allotropes of element X.
61 Two organic compounds A and B have the same molecular formula C6H12. Write the names and structural formulae:

(a) if A is cyclic compound


(b) if B is an open chain compound


(c) Which compound contains single bonds as well as a double bond?


(d) Which compound contains only single bonds?
62 The solid element A exhibits the property of catenation. It is also present in the form of a gas B in the air which is utilized by plants in photosynthesis. An allotrope C of this element is used in glass cutters.

(a) What is element A?


(b) What is the gas B?


(c) Name the allotrope C.


(d) State another use of allotrope C (other than in glass cutters)


(e) Name another allotrope of element A which exists as spherical molecules.


(f) Name a yet another allotrope of element A which conducts electricity.
63 An element E exist in three allotrope forms A, B and C. in allotrope A, the atoms of element E are joined to form a sheet like structure. In allotrope B, each atom of element E is surrounded by four other E atoms to form a rigid structure.

(a) Name the element E.


(b) What is allotrope A?


(c) What is allotrope B?


(d) What is allotrope C?


(e) Which allotrope is used in making jewellery?


(f) Which allotrope is used in making anode of a dry cell?
64 You are given the following molecular formulae of some hydrocarbons:

C5H8; C7H14; C5H10; C7H12; C6H12;


(a) Which formula represent cyclohexane as well as hexane?


(b) Which formula represent benzene?


(c) Which three formulae represent open chain


(d) Which two formulae represent unsaturated hydrocarbons having double bonds?


(e) Which three formulae can represent cyclic hydrocarbons?
65 Which of the following compounds can have a triple bond?

C2H4, C3H4, C3H6,
66 Write the molecular and structural formula of a cyclic hydrocarbon whose molecule contains 8 atoms of carbon.
67 What is the molecular formula and structural formula of a cyclic hydrocarbon whose one molecule contains 8 hydrogen atoms?
68 Write the molecular formula of: (i) an alkane (ii) an alkene, and (iii) an alkyne, each having 20 carbon atoms?
69 Which of the following compounds can have a double bond?

C4H10; C5H8; C5H10;
70 Which of the following hydrocarbons is unsaturated?

C3H4; C2H6;

Very Short Answer Type Questions-Pg-239

1 Write the molecular formula of ethanol.
2 What is the next higher homologue of methanol (CH3OH)?
3 Identify the functional group present in the following compound and name it according to IUPAC system: CH3OH
4 Give the common name and IUPAC name of the simplest aldehyde.
5 What is the common name of methanol?
6 Write the names of the following functional group:

(a)


(b)

7 Name the simplest ketone.
8 What is the common name of propanone?
9 Write the IUPAC names of the following:

(i) CH3COCH3


(ii) CH3COCH2CH3
10 Write the name and chemical formula of the simplest organic acid.
11 Write the IUPAC names, common names and formulae of the first two members of the homologous series of carboxylic acids.
12 What is the common name of:

(a) methanoic acid, and (b) ethanoic acid?
13 Draw the structure for the following compounds:

(a) Ethanoic acid (b) Propanoic acid
14 Give the common names and IUPAC names of the following compounds:

(a) HCOOH


(b) CH3COOH
15 Give the name and structural formula of one homologue of HCOOH.
16 Write the formulae of:

(a) methanoic acid, and


(b) ethanoic acid.
17 Give the common name and IUPAC name of C2H5OH.
18 Give the IUPAC name of the following compound:

C3H7OH
19 Give the name and structural formula of one member of the following:

Alcohols
20 Give IUPAC name of the following compounds:

(a) C4H9OH


(b) C5H11OH
21 What is the common name of ethanol?
22 What is the difference between two consecutive homologues:

(i) in terms of molecular mass?


(ii) in terms of number and kind of atoms per molecule?
23 What type of fuels:

(a) burn with a flame?


(b) burn without a flame?
24 State whether the following statements is true or false:

The minimum number of carbon atoms in a ketone molecule is two.
25 Fill in the following blanks with suitable words:

(a) The next higher homologues of ethanol is ………………


(b) The next homologues of C2H5OH is ……………………………….


(c) The next higher homologues of ethane is …………………………..


(d) The functional group present in ethanol is ………………………..


(e) Organic compounds having ----- PICTURE---- OH functional group are known as ………………………….

Short Answer Type Questions-Pg-240

26 Give the general name of the class of compounds having the general formula CnH2n-2. Write name of the first member of this homologues series.
26 The general formula of a homologues series of carbon compounds is CnH2n. Write the molecular formulae of the second and fourth members of the series.
26 Write the molecular formulae of the third and fifth members of homologues series of carbon compounds represented by the general formula CnH2n+2
27 (a) Give the names and structural formulae of the next two higher homologues of methane.

(b) The molecular formula of a hydrocarbon is C2H5. Name its homologues series.


(c) Select the hydrocarbons which are members of the same homologues series. Give the name of each series. C5H10; C3H8; C4H10; C7H12; C8H16
28 (a) Give the molecular formula of one homologue of each of the following:

(i) C3H6


(ii) C2H6


(iii) C2H2
28 What is the difference in the molecular mass of any two adjacent homologues?
28 By how many carbon atoms and hydrogen atoms do any two adjacent homologues differ?
29 Write the formula of the functional group present in carboxylic acids.
29 Name the functional group present in CH3 – C ≡ CH.
29 Name the functional groups present in the following compounds

(i) CH3CHO (ii) CH3CH2COOH (iii) CH3COCH3 (iv) CH3CH2CH2OH
30 Write the IUPAC name and common name of CH3CI.
30 Draw the structure of chlorobutane.
30 Draw the structure for bromopentane. Are structural isomers possible for bromopentane?
31 Write the name and formula of an organic compound containing a ketone functional group.
31 Write the names and formulae for the first three members of the homologues series of chlorolkanes.
31 How would you name the following compound?

CH3-CH2-BR
32 What is the general name of the organic compounds containing the- group.
32 Which of the following compounds contains a carboxylic acid group?

CH3OH, CH3COOH, CH3CHO, CH3COCH3
32 How would you name the compound?

HCOOH
33 Define a homologues series. Give the name and structural formula of one homologues of the following:

CH3OH
33 Write the molecular formula of the third member of the homologues series of carbon compounds with general formula CnH2n+1OH.
33 Name any two fossil fuels.
34 Draw the structure for the following compounds:

(i) Propanone (ii) Butanone
34 Write the IUPAC names of the following:

(i) HCHO (ii) CH3CHO (iii) CH3CH2CHO (iv) CH3CH2CH2CHO
34 Which functional group is likely to be present in an organic compound having the molecular formula C4H10O? Write formula of the organic compound.
35 (a) Match the formulae in group A with appropriate names from group B:

Group A: CH3COOH, CH3CHO, CH3OH


Group B: Ethanol, Methanol, Ethanal, Ethanoic acid
35 Draw the structure of butanoic acid.
35 What is the IUPAC name of acetic acid ?
36 Which functional group do you think can be present in an organic compound having the molecular formula C5H10O2? Write the formula of the organic compound.
36 Give one example each of the compounds having the following functional groups:

(i) Aldehyde group (ii) Alcohol group (iii) Carboxylic acid group (iv) Halo group
36 Give one example each of the compounds having the following functional groups:

(i) Aldehyde group


(ii) Alkyne group
37 What is the molecular formula and structure of the alcohol which can be thought to be derived from pentane?
37 Write the names of the following functional groups:

(i) –CHO (ii) –OH (iii) –COOH (iv) C=O (v)

37 What makes the candle flame yellow and luminous?

Long Answer Type Questions-Pg-241

38 What is homologues series? Explain with an example.
38 State two characteristics of a homologous series.
38 The molecular formula of an organic compound is C18H36. Name its homologous series.
38 Select the hydrocarbons which belong to the same homologous series. Give the name if of each series.

CH4, C2H2, C2H4, C2H6, C4H10, C3H4, C3H6,
38 What is meant by ‘heteroatom’? Give examples. Write the names and formulae of two organic compounds containing different heteroatoms.
39 What is meant by a functional group? Explain with an example.
39 Write three common functional groups present in organic compounds. Give their symbols/formulae.
39 Name the functional groups present in the following compounds:

(i) CH3COOH (ii)CH3CH2CH2CHO (iii) C2H5OH (iv) CH3COCH2CH3
39 Name the functional group which always occurs in the middle of a carbon chain.
39 Draw the structures for the following compounds:

(i) Ethanal (ii) Propanal (iii) Butanal (iv) Pentanal
40 What happens when carbon burns in air? Write the chemical equation of the reaction which takes place.
40 Why are coal and petroleum called fossil fuels?
40 Explain how coal was formed in the earth.
40 Describe how petroleum was formed in the earth.
40 Name a fossil fuel other than coal and petroleum.

Multiple Choice Questions (MCQs)-Pg-242

41 The molecular formula of a homologue of butane is:
42 One of the following molecular formula can represent two organic compounds having different functional groups. This molecular formula is :
43 The number of carbon atoms present in the molecule of fifth member of the homologous series of alkynes is:
44 One of the following burns without producing a flame. This is:
45 The functional group which always occurs in the middle of a carbon chain is :
46 The molecular formulae of some organic compounds are given below. Which of these compounds contains an aldehyde group?
47 The organic compounds which are isomeric with one another are:
48 The fuel which usually burns with a blue flame is:
49 Which of the following burns by producing a yellow, luminous flame?
50 The molecular formula of an organic compound is C48H94. This compound belongs to the homologous Series of:
51 One of the following molecular formulae represent a ketone. This formula is:
52 Which one of the following is not a fossil fuel?
53 Butanone is a four-carbon compound having the functional group:
54 The molecular formula of the third member of the homologous series of ketones is:
55 The functional group present in propanal is:

Questions Based on High Order Thinking Skills (HOTS)-Pg-243

56 An organic compound having the molecular formula C3H6O can exist in the form of two isomers A and B having different functional groups. The isomer A is a liquid which is used as a solvent for nail polish. The isomer B is also a liquid. An aqueous solution of one of the lower homologues of B is used for preserving biological specimens in the laboratory

(a) What is compound A?


(b) Write the electron-dot structure of A.


(c) What is compound B?


(d) Write the electron-dot structure of B.


(e) Name the lower homologue of compound B which is used in preserving biological specimens.
57 A hard material X which is mined from the earth is used as a household fuel and also for the generation of electricity at Thermal Power Stations. A soft material Y is also used as a fuel in the form of candles. A gaseous material Z which occurs along with petroleum is increasingly being used as a fuel in running vehicles in its compressed form.

(a) What are materials, X, Y and Z?


(b) When materials X, Y and Z are burned separately:


(i) Which material burns by producing a yellow, luminous flame?


(ii) Which material ultimately bums without producing a flame?


(iii) Which material can bum in a gas stove by producing a blue flame?
58 Three organic compounds A, B and C have the following molecular formulae:

A) C4H8O2


B) C4H10O


C) C4H8O


(a) Which compound contains an alcohol group? Write its name and structural formula.


(b) Which compound contains a carboxyl group? Write its name and structural formula.


(c) Which molecular formula can represent an aldehyde as well as a ketone? Write the names and structural formulae of the aldehyde and ketone represented by this molecular formula.
59 A colourless organic liquid X of molecular formula C2H4O2 turns blue litmus to red. Another colourless organic liquid Y of molecular formula C3H6O has no action on any litmus but it is used as a nail polish remover. A yet another colourless organic liquid Z of molecular formula C3H6O has also no action on litmus but it is used in tincture of iodine.

(a) Name the liquid X. To which homologous series does it belong? Give the name of another member of this homologous series.


(b) Name the liquid Y. To which homologous series does it belong? Write the name of another member of this homologous series.


(c) Can you name an organic compound having the same molecular formula as liquid Y but which belongs to a different homologous series? What is this homologous series?


(d) Name the liquid Z. To which homologous series does it belong? Write the name of another member of this homologous series.
60 You are given an organic compound having the molecular formula C3H8• Give the name and formula of the compound formed:

(a) when one H atom of C3H8 is replaced by a Cl atom.


(b) when one H atom of C3H8 is replaced by OH group.


(c) when one H atom of C3H8 is replaced by a CHO group.


(d) when one H atom of C3H8 is replaced by a COOH group.


(e) when two H atoms joined to the middle carbon atom of C3H8 are replaced by one O atom.

Very Short Answer Type Questions-Pg-262

1 Name the gas evolved when ethanoic acid is added to sodium carbonate. How would you prove the presence of this gas?
2 Which of the following will give brisk effervescence with sodium hydrogen carbonate and why?

CH3COOH, CH3CH2OH
3 Name the functional group present in an organic compound which gives brisk effervescence with NaHCO3•
4 Name the hydrocarbon formed when ethanol is heated with cone. H2S04 at 170 �C? What is this reaction known as?
5 Why does ethyne (acetylene) burn with a sooty flame?
6 Name the product formed when hydrogen is added to ethene.
7 Explain why, ethene decolourises bromine water whereas ethane does not.
8 Name two catalysts which can be used in the hydrogenation of unsaturated compounds.
9 State two disadvantages of incomplete combustion.
10 What happens when (give chemical equation): Sodium reacts with ethanol (ethyl alcohol)
11 Describe one reaction of ethanol.
12 Name one liquid carbon compound which is being used as an additive in petrol in some countries.
13 What are the raw materials required for making soap in a laboratory (or at home)?
14 Would you be able to check whether water is hard by using a detergent? Why?
15 Describe a test for carboxylic acids.
16 Why is the conversion of ethanol into ethanoic acid an oxidation reaction?
17 Explain why, alkanes are excellent fuels.
8 Name one chemical compound which can be used to distinguish between ethanol and ethanoic acid.
19 Complete the following equations:

(a) CH3CH2OH -----PICTURE


(b) CH3CH2OH + C2H5OH

20 Complete and balance the following equations:

(a) CH4 + O2


(b) CH4 + Cl2
21 Fill in the following blanks with suitable words:

(a) The process of burning of a hydrocarbon in the presence of air to give CO2, H20, heat and light is known as ............


(b) The sodium salt of a long chain fatty acid is called .........


(c) ............ is better than soap for washing clothes when the water is hard.


(d) The organic acid present in vinegar is.............

Short Answer Type Questions-Pg-263

22 Which of the following hydrocarbons will give substitution reactions and why?

CH4, C3H6, C3H8, C4H6, C5H12, C5H10
23 Which of the following will give addition reactions and why?

C4H10, C2H6, C2H4, CH4, C3H8, C3H4
24 Write the chemical equation of the reaction which takes place during the burning of ethanol in air.
24 Why is ethanol used as a fuel?
24 State two uses of ethanol (other than as a fuel).
25 What happens when propanoic acid is warmed with methanol in the presence of a few drops of concentrated sulphuric acid? Write equation of the reaction involved.
25 What change will you observe if you test soap solution with a litmus paper (red and blue)? Give reason for your observation.
25 What is meant by denatured alcohol? What is the need to denature alcohol?
26 How would you test for an alcohol?
26 Give the harmful effects of drinking alcohol.
26 Explain why, methanol is much more dangerous to drink than ethanol.
27 How would you convert:

(a) ethanol into ethene?


(b) propanol into propanoic acid?


Name the process in each case and write the equations of the reactions involved.
28 Give reasons for the following observations:

(a) Air holes of a gas burner have to be adjusted when the vessels being heated get blackened by the flame.


(b) Use of synthetic detergents causes pollution of water.
29 What would be observed on adding a 5% alkaline potassium permanganate solution drop by drop to some warm ethanol in a test-tube? Write the name of the compound formed during the chemical reaction. Also write chemical equation of the reaction which takes place.
29 How would you distinguish experimentally between an alcohol and a carboxylic acid on the basis of a chemical property?
30 Name the functional group of organic compounds that can be hydrogenated. With the help of a suitable example, explain the process of hydrogenation, mentioning the conditions of the reaction and any one change in physical property with the formation of the product. Name any one natural source of organic compounds that are hydrogenated.
31 Name the gas evolved when ethanol reacts with sodium.
31 What type of compound is formed when a carboxylic acid reacts with an alcohol in the presence of cone.H2SO4?
31 What will you observe when dilute ethanoic acid and dilute hydrochloric acid are put on universal indicator paper, one by one? What does it show?
32 What type of compound is CH3COOH?
32 What substance should be oxidised to prepare CH3COOH?
32 What is the physical state of CH3COOH?
32 State one advantage of soaps over detergents.
33 What happens when ethanol reacts with ethanoic acid in the presence of a little of concentrated sulphuric acid? Write equation of the reaction involved.
33 What happens when ethanol is heated with concentrated sulphuric acid at 170 �C? Write the equation of the reaction which takes place.
34 What happens when ethanol is oxidised with alkaline potassium permanganate (or acidified potassium dichromate) ? Write the equation of the reaction involved.
34 Choose those compounds from the following which can tum blue litmus solution red: HCHO, CH3COOH, CH3OH, C2H50H, HCOOH, CH3CHO

Give reasons for your choice.
35 Explain the process of preparation of soap in laboratory.
35 Why is common salt (sodium chloride) added during the preparation of soap?
35 Why is soap not suitable for washing clothes when the water is hard?
36 What happens when methane (natural gas) bums in air? Write the chemical equation of the reaction involved.
36 What happens when ethanoic acid reacts with sodium carbonate? Write chemical equation of the reaction involved.
36 Give a test that can be used to differentiate chemically between butter and cooking oil.
37 Describe, giving equation, a chemical reaction which is characteristic of saturated hydrocarbons (or alkanes).
37 What is an oxidising agent? Name two oxidising agents which can oxidise ethanol to ethanoic acid.
37 Describe one reaction of a carboxylic acid.
38 Write names and formulae of hydrocarbons containing a single and a double bond (one example for each). Give one characteristic chemical property of each.
38 What is a detergent? Name one detergent.
38 Why have detergents replaced soap as a washing agent ?
39 (a) How does ethanoic acid react with sodium hydrogencarbonate? Give equation of the reaction which takes place.
39 Why are carbon and its compounds used as fuels for most applications?
39 Which of the two is better for washing clothes when the water is hard: soap or detergent? Give reason for your answer.
40 What is meant by a substitution reaction? Give an example (with equation) of the substitution reaction of an alkane.
40 How is soap made? Write a word equation involved in soap making.
41 How is ethanoic acid obtained from ethanol? Write down the chemical equation of the reaction involved.
41 How would you distinguish between ethanol and ethanoic acid by chemical test?
41 Explain the formation of scum when hard water is treated with soap.
42 What happens when methane reacts with chlorine? Give equation of the reaction which takes place.
42 What is hydrogenation? What is its industrial application?
42 Give any two differences between soaps and detergents.
43 What happens when ethanoic acid reacts with sodium hydroxide? Write equation of the reaction involved.
43 What happens when vegetable oils are hydrogenated? Name the catalyst used.
43 What is the advantage of detergents over soaps for washing clothes? Also state One disadvantage.
44 An organic compound X of molecular formula C2H4O2 gives brisk effervescence with sodium hydrogencarbonate. Give the name and formula of X.
44 A mixture of ethyne (acetylene) and oxygen is burnt for welding. Can you tell why a mixture of ethyne and air is not used?
44 Name a chemical reaction which is characteristic of unsaturated hydrocarbons (like alkenes and alkynes).
45 What is meant by an addition reaction? Give an example (with equation) of an addition reaction of an alkene.
45 What is added to groundnut oil when it is to be converted to vanaspati ghee?
45 Which of the two is better for our health: butter or vegetable oil? Why?

Long Answer Type Questions-Pg-265

46 When ethanoic acid reacts with sodium hydrogencarbonate, then a salt X is formed and a gas Y is evolved. Name the salt X and gas Y. Describe an activity with the help of a labelled diagram of the apparatus used to prove that the evolved gas is the one which you have named. Also write the chemical equation of the reaction involved.
46 Give any two uses of ethanoic acid.
47 Esters are sweet-smelling substances and are used in making perfumes. Describe an activity for the preparation of an ester with the help of a well labelled diagram. Write an equation for the chemical reaction involved in the formation of the ester. Also, write the names of all the substances involved in the process of esterification.
47 State any two uses of esters.
48 Name the reaction which is usually used in the conversion of vegetable oils to fats. Explain the reaction involved in detail. Write a chemical equation to illustrate your answer.
48 What is saponification? Write the chemical equation of the reaction involved in this process. Name all the substances which take part in this process and also those which are formed.
48 Why does micelle formation take place when soap is added to water? Will a micelle be formed in other solvents like ethanol also?
49 What is a soap? Name one soap.
49 Describe the structure of a soap molecule with the help of a diagram.
49 Explain the cleansing action of soap. Draw diagrams to illustrate your answer.

Multiple Choice Questions (MCQs)-Pg-265

50 While cooking, if the bottom of the cooking utensil is getting blackened on the outside, it means that :
51 When ethanol is heated with alkaline potassium permanganate solution, it gets converted into ethanoic acid. In this reaction, alkaline potassium permanganate acts as :
52 When ethanol is heated with concentrated sulphuric acid at 170 �C, it gets converted into ethene. In this reaction, concentrated sulphuric acid acts as :
53 When a vegetable oil is treated with hydrogen in the presence of nickel (or palladium) catalyst, it forms a fat. This is an example of:
54 The soap molecule has a:
55 Chlorine reacts with saturated hydrocarbons at room temperature in the:
56 In a soap micelle, the soap molecules are arranged radially with:
57 When ethanol reacts with sodium metal, it forms two products. These products are:
58 Vinegar is a solution of about:
59 One of the following substances is not added to make denatured alcohol. This is:
60 One of the following organic compounds cannot decolourise the red-brown colour of bromine water. This compound is:

Options||A. C14H28


B. C7H12


C. C6H14


D.C9H16
61 The substance which can produce brisk effervescence with baking soda solution is :
62 The chemical which is not required for the preparation of soap in the laboratory is:
63 Which of the following can damage optic nerve leading to blindness, if taken internally?
64 The usual disease caused by the excessive drinking of alcohol over a long period of time is:
65 Which of the following molecular formula corresponds to ethyl butanoate ester?

Questions Based on High Order Thinking Skills (HOTS)-Pg-266

66 A neutral organic compound X of molecular formula C2H6O on oxidation with acidified potassium dichromate gives an acidic compound Y. Compound X reacts with Y on warming in the presence of cone. H2SO4 to give a sweet smelling substance Z. What are X, Y and Z?
67 Consider the following organic compounds:

HCHO, C2H5OH, C2H6, CH3COOH, C2H5Cl


Choose two compounds which can react in the presence of cone. H2SO4 to form an ester. Give the name and formula of the ester formed.
68 A neutral organic compound is warmed with some ethanoic acid and a little of cone. H2SO4. Vapours having sweet smell (fruity smell) are evolved. What type of functional group is present in this organic compound?
69 The structural formula of an ester is:


Write the formula of the acid and the alcohol from which it is formed.
70 Consider the following organic compounds:

CH3OH, C2HsOH, CH3COCH3, CH3COOH, C2H5COOH, C4H9COOC2H5, CH4, C2H6, CH3CHO, HCHO


Out of these compounds:


(a) Which compound is most likely to be sweet-smelling?


(b) Which compound on treatment with cone. H2SO4 at 170 �C forms an alkene?


(c) Which compound on repeated chlorination forms chloroform?


(d) Which compound is added to alcohol to denature it?


(e) Which compound is a constituent of vinegar?


(f) Which compound is used to sterilise wounds and syringes?
71 An organic acid X is a liquid, which often freezes during winter time in cold countries, having the molecular formula C2H4O2. On warming it with methanol in the presence of a few drops of concentrated sulphuric acid, a compound Y with a sweet smell is formed.

(a) Identify X and Y. Also write their formulae showing the functional group present in them.


(b) Write a chemical equation for the reaction involved.
72 An organic compound A having the molecular formula C3H8O is a liquid at room temperature. The organic liquid A reacts with sodium metal to evolve a gas which bums causing a little explosion. When the organic liquid A is heated with concentrated sulphuric acid at 170 �C, it forms a compound B which decolourises bromine water. The compound B adds on one molecule of hydrogen in the presence of Ni as catalyst to form compound C which gives substitution reactions with chlorine.

(a) What is compound A?


(b) What is compound B?


(c) What type of reaction occurs when A is converted into B?


(d) What is compound C?


(e) What type of reaction takes place when B is converted into C?
73 An organic compound A (molecular formula C2H4O2) reacts with Na metal to form a compound B and evolves a gas which burns with a pop sound. Compound A on treatment with an alcohol C in the presence of a little of concentrated sulphuric acid forms a sweet-smelling compound D (molecular formula C3H6O2). Compound D on treatment with NaOH solution gives back B and C. Identify A, B, C and D.
74 Which of the following hydrocarbons can decolourise bromine water and which cannot? Why?

C6H12, C6H14, C6H10
75 A four carbon atoms containing neutral organic compound X reacts with sodium metal to evolve a gas which burns with a 'pop' sound. Another four carbon atoms containing carbon compound (Y) reacts with sodium hydrogencarbonate to evolve a gas which turns lime water milky. When compounds X and Y are heated together in the presence of a little of concentrated sulphuric acid, then a new compound Z is formed.

(a) What is compound X? Also write its formula.


(b) What is compound Y? Also write its formula,.


(c) What is compound Z? Also write its formula.


(d) What type of smell is given by compound Z?


(e) What is the general name of compounds like Z?


(f) What is the general name of the reaction which takes place between X and Y to form Z?