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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 51. |
The number of carbon atoms joined in a spherical molecule of bukminsterfullerence is :A. fiftyB. sixtyC. seventyD. ninety |
| Answer» Correct Answer - B | |
| 52. |
Which of the following cannot exhibit isomerism?A. `C_(4)H_(10)`B. `C_(5)H_(12)`C. `C_(3)H_(8)`D. `C_(6)H_(14)` |
| Answer» Correct Answer - C | |
| 53. |
A hydrocarbon molecule has 3 carbon atoms . Write down its molecualr formula if it is an : (i) alknae , (ii) alkene, (iii) alkyne. |
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Answer» The number of carbon atoms in the molecule of this hydrocarbon is 3, that is , n =3 (i) The general foumula of an alkane is `C_(n)H_(2n+2)` where n is the number of carbon atoms in one molecule of the alkane. Here , n =3 so putting n=3 in this general foumula we get `C_(3)H_(2xx3+2) or C_(3)H_(8)` .Thus the molecular formula of hte given hydrocarbon if it is an alkane is `C_(3)H_(8)`. please solve the remaining two parts of this problem yourself . The answers wil be `C_(3)H_(6)` for alkene and `C_(3)H_(4)` for alkyne. |
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| 54. |
Which of the following is not a straight chain hydrocarbon ?A. `CH_(3)-CH_(2)-CH_(2)-underset(CH_(3))underset(|)(C)H_(2)`B. `H_(3)C-CH_(2)-CH_(2)-CH_(2)-CH_(3)`C. `H_(2)overset(H_(3)C)overset(|)(C)-H_(2)C-H_(2)C-CH_(3)`D. |
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Answer» Correct Answer - D It is the correct answer. |
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| 55. |
The number of isomers formed by the hydrocarbon with molecular formula `C_(5)H_(12) ` is :A. 2B. 5C. 3D. 4 |
| Answer» Correct Answer - C | |
| 56. |
The hydrocarbon which has alternate single and double bonds arranged in the from of ring is :A. cyclobutaneB. benzeneC. buteneD. hexene |
| Answer» Correct Answer - B | |
| 57. |
Which amond the following are unsaturated hydrocarbons ? (i) `H_(3)C-CH_(2)-CH_(2)-CH_(3)` (ii) `H_(3)C-C-=C-CH_(3)` (iii) `H_(3)C-underset(CH_(3))underset(|" ")(CH)-CH_(3)` (iv) `H_(3)C-underset(CH_(3))underset(|)C=CH_(2)`A. (i) and (iii)B. (ii) and (iii)C. (ii) and (iv)D. (iii) and (iv) |
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Answer» Correct Answer - C Unsaturated hydrocarbons have double or triple bond in the structure. Both (ii) and (iv) structures have triple and double carbon-carbon bonds respectively. |
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| 58. |
Which of the following hydrocarbons undergo addition reactions: `C_(2)H_(6), C_(3)H_(8), C_(3)H_(6), C_(2)H_(2)" and "CH_(4)`. |
| Answer» The unsaturated hydrocarbons (alkenes and alkynes) undergo additionn reactions. Out of the above hydrocarbons `C_(3)H_(6)` is and alkene whereas `C_(2)H_(2)` is an alkyne . So,`C_(3)H_(6) "and" C_(2)H_(2)` will undergo addition rections. | |
| 59. |
how do the melting and boiling points o the hydrocarbons change with increase in molecular mass? |
| Answer» There increase because of the increase in the molecular size. As a result, the intermolecular forces of attraction increase. | |
| 60. |
Write the sturctural formulae of any tow isomers of hexane `(C_(6)H_(14)`, other than n hexane. |
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Answer» Hexane `(C_(6)H_(14))` has 6 carbon atoms in its mlecule. Since we are not supposed to write the sturctural formula of n-hexane (normal hexane), so we cannot put all the 6 carbon atoms in one straight chain Now , first we write 5 crbon atoms in one straight chin and the remaining 1 carbon atom in side chain to obtain one isomer of hexane (called 2-methypentane)[see Figure 25(a)]. Then we write 4 carbon atoms in one atraight chain and the remaining 2 carbon atoms in two side chain and the remaining 2 carbon atoms in two side chains to get the second isomer (called 2,3 dimethylbutane)[see Figure 25(b)] Before we go further and describe the classification of organic compounds intio homologous series, |
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| 61. |
Write the structural formulae of all isomers of hexane. |
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Answer» Hexane has the following five isomers (i) `CH_(3)-underset("n-hexane")(CH_(2)-CH_(2))-CH_(2)-CH_(2)-CH_(3)` (ii) `overset(1)CH_(3)-underset("2-methyl pentane")underset(CH_(3))underset(|)(overset(2)CH)-overset(3)CH_(2)-overset(4)CH_(2)-overset(5)CH_(3)` (iii) `overset(1)CH_(3)-underset("3-methyl pentane")(overset(2)CH_(2)-underset(CH_(3))underset(|)overset(3)CH)-overset(4)CH_(2)-overset(5)CH_(3)` (iv) `underset("2,3-dimethyl butane")(overset(1)CH_(3)underset(CH_(3))underset(|)(-overset(2)CH)underset(CH_(3))underset(|)(-overset(3)CH-)overset(4)CH_(3))` (v) `underset("2,3-dimethyl butane")(overset(1)(C)H_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(overset(2)(C))-overset(3)CH_(2)-overset(4)CH_(3)` |
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| 62. |
(a) Give a chemical test to distinguish between saturated and unsaturated hydrocarbons. (b) name the products formed when ethanol burns in air. List two forms of energy that are liberated on burning ethanol. (c). Why is the reaction between methane ad chlorine considered to be a substitution reaction? |
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Answer» (a) Pass the vapours of given samples of the hydrocarbons into bromine water taken in two separate test tubes. The sample which discharge the colour of brominie water is that of unsaturated hydrocarbon while the one which does not discharge the colour of bromine water, represents saturated hydrocarbon. (b) On burning ethanol in excess of air, product is a mixture of carbon dioxide and water vapours. both heat and light are evolved in the combustion reaction. `C_(2)H_(5)OH(l)+underset((Air))(3O_(2)(g))to2CO_(2)(g)+3H_(2)O(g)+heat+light` (c) When methane is reacted with chlorine in the presence of sun light, tetrachloromethane is formed as the product. it is considered as substitution reaction because all the four hydrogen atoms attached to carbon atom are replaced by chlorine atoms. `underset("Methane")(CH_(4)(g))+4Cl_(2)(g)tounderset("Tetrachloromethane")(C Cl_(4)(g))+4HCl(g)` |
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| 63. |
What is the role of metal or reagents written on arrows in the given chemical reactions ? (a) (b) `CH_(3)COOH+CH_(3)CH_(2)OHoverset("Conc.H_(2)SO_(4))toCH_(3)COOC_(2)H_(5)+H_(2)O` (c ) `CH_(3)CH_(2)OHunderset("Heat")overset("Alk."KMnO_(4))toCH_(3)COOH` |
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Answer» (a) Nickel (Ni) acts as a hydrogenation catalyst for the reaction. (b) Conc. `H_(2)SO_(4) ` removes a molecule of `H_(2)O` from the reaction mixture and acts as a dehydrating agent. (c) Alkaline `KMnO_(4)` acts as an oxidising agent and oxidises alcohol to ethanoic acid. |
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| 64. |
(a) What are hydrocarbons ? Give examples. (b) Give the structural differences between saturated and unsaturated hydrocarbons with two examples each. (c ) What is functional group ? Examples of four different functional groups. |
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Answer» (a) Hydrocarbons are the organic compounds containing only carbon and hydrogen atoms as their constituents. These may be alkanes, alkenes and akynes. (b) Saturated hydrocarbons or alkanes contains either C-C and C-H bonds in their molecules. These are represented by the general formula `C_(n)H_(2n+2)`. for example. `underset("Ethane")(H-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-H)" "underset("Propane")(H-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-H)` Unsaturated hydrocarbons contain either atleast one `gtC=Clt` bond or triple `-C-=C-` bond in their molecules. these may be either alkenes or alkynes in nature. the general formula of alkenes is `C_(n)H_(2n)` while that of alkynes is `C_(n)H_(2n-2)`. for example. `underset("Ethene")(H-overset(H)overset(|)(C)-=overset(H)overset(|)(C)-H)" "underset("Propene")(H-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)(C)=underset(H)underset(|)(C)-H)" "underset("Ethyne")(H-C-=C-H)" "underset("Propyne")(H-underset(H)underset(|)overset(H)overset(|)(C)-C-=C-H)` (c) For the definition of functional group and example. |
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| 65. |
A compound with molecular formula `C_(2)H_(6)O` is used as a fuel. Identify the compound. |
| Answer» The compound is ethanol with formula `C_(2)H_(5)OH`. | |
| 66. |
Name the reaction which is commonly used in the conversion of vegetable oil to fats. Explain the reaction involved in detail. |
| Answer» The reaction is known as catalytic hydrogenation. | |
| 67. |
Oils on treating with hydrogen in the presence of palladium or nickel catalyst from fats. This is an example ofA. addition reactionB. substitution reactionC. Displacement reactionD. Oxidation reaction |
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Answer» Correct Answer - A Oils are unsaturated in nature. The reaction is known as hydrogenration of oils. By the addition of hydrogen, they become saturated. Therefore, it is an addition reaction. |
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| 68. |
One of the following substances is not added to make denatured alchol.This is:A. methyl alcoholB. copper suphateC. chloroformD. pridine |
| Answer» Correct Answer - (c ) | |
| 69. |
What are oxidising agents? |
| Answer» Oxidising agents are the substances that gain electrons in redox reaction and whose oxidation number is reduced. | |
| 70. |
Which of the following belong to the same homeologous series ? `C_(3)H_(8),C_(3)H_(6),C_(4)H_(8),C_(4)H_(6)` |
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Answer» All these compounds are hydrocarbons , so all that we have to do is to find out which of them alre alkanes ,alkanes and lakynes . (i) `C_(3)H_(8) "corresponds to the general formula for alknaes" C_(n)H_(2n+2)(with n=3), "therefore", C_(3)H_(89)` is an alkane. (ii) `C_(3)H_(6) "and" C_(4)H_(8) "correspond ot the general formula for alkenes" C_(n)H_(2n)` (with n=3 and n=4 respectively)," therefore" , `C_(3)H_(6) "and"C_(4)H_(8)` both alkenes. (iii)`C_(4)H_(6) "corresponds ot the general formula for alkynes" C_(n)H_(2n-2)(with n=4), " therefore" C_(4)H_(6)` is a alkyne. |
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| 71. |
Give the formula and name of the alkane which contains four carbon atoms in the molecule. |
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Answer» The alkane with four cabon atoms in butane. `H-underset(H)underset(|)overset(H)overset(|)(C)-underset((C_(4)H_(10)))(underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-H,` IUPAC name : Butane |
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| 72. |
Give the electron dot structure of chloromethane. Also write the formula and the name of the next homologue of it. |
| Answer» `H:underset(H)underset(..)overset(Cl)overset(..)(C):Hunderset("Chloromethane")(or)H-underset(H)underset(|)overset(Cl)overset(|)(C)-H" "H:underset(H)underset(..)overset(H)overset(..)(C):underset(H)underset(..)overset(Cl)overset(..)(C):H" "underset("Chloromethane")(or" "H-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(Cl)overset(|)(C)-H)` | |
| 73. |
Write the structural formula of hexanal. |
| Answer» `H-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-underset(H)underset(|)overset(H)overset(|)(C)-overset(O)overset(||)(C)-H` | |
| 74. |
Which of the following belong to the same homologous series? `C_(3)H_(8),C_(4)H_(8),C_(4)H_(6),C_(3)H_(6)`. |
| Answer» `C_(3)H_(6) and C_(4)H_(8)` belong to the same homologous series which is alkenes with general formula `C_(n)H_(2n)`. | |
| 75. |
Which of the following compounds can have a triple bond? `C_(2)H_(4),C_(3)H_(4),C_(3)H_(6)` |
| Answer» `C_(3)H_(4)` has triple bond with the formula `CH_(3)C-=CH` | |
| 76. |
Which of the following compunds can have a double bond? `C_(3)H_(8),C_(3)H_(6)` |
| Answer» The compoiund having a double bond is called an alkene. So , all tht we have to do here is to find out which of the above given compounds is an alkene.Here `C_(3)H_(6)` is an alkene (because it correstponds to the general formula for alkenes `C_(n)H_(2n)` with n=3 Thus , the compound `C_(3)H_(6))` will have a double bond in it . | |
| 77. |
What is an homologous series? Which two of the following organic compounds belong to te same homologous series? `C_(2)H_(6),C_(2)H_(6)O,C_(2)H_(6)O_(2),CH_(4)O` |
| Answer» For the definition of homologous series. The compounds `CH_(3)O and C_(2)H_(6)O` belong to the same homologous series known as alkanols. | |
| 78. |
Which of the following organic compounds is undaturated? `(CH_(4),C_(2)H_(4)` |
| Answer» We know that alkenes and alkynes are unsaturated compounds. So all that we have to do here is to find out which of the above compounds is an alkene or alkyne. That will be the undaturated compound . Now out of the above ocmounds , `C_(2)H_(4)` is unsaturated (beacuse it is an alkene corresponding to the general formula of alkenes `C_(n)H_(2n) "with" n=2)` | |
| 79. |
Coke can be used asA. an oxidizing agentB. a household fuelC. printer inkD. electrodes. |
| Answer» Correct Answer - B | |
| 80. |
Carbon exists in the atmosphere in the from ofA. carbon monoxide onlyB. carbon monoxide and carbon dioxide in tracesC. carbon dioxide onlyD. coal gas. |
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Answer» Correct Answer - B Both CO and `CO_(2)` gases are present in traces in the atmosphere. |
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| 81. |
What change will you observe if you test soap with litmus paper (red and blue)? |
| Answer» Since soap is basic in nature, it will turn red litmus blue. However, the colour of blue litmus will remain blue. | |
| 82. |
The IUPAC name of the compound `CH_(3)-CH_(2)-CHO` isA. PropanalB. PropanoneC. EthanolD. Ethanal |
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Answer» Correct Answer - A It is the correct answer. |
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| 83. |
A hydrocarbon having one double bond has 100 crbon atoms in its molecule . The number of hydrogen atoms in its molecule will be:A. 200B. 198C. 202D. 196 |
| Answer» Correct Answer - A | |
| 84. |
Write a chemical test to distinguish between ethanol ad ethanoic acid. |
| Answer» Ethanoic aciid turns blue litmus red but ethanol fails to do so. | |
| 85. |
How would you name the following compounds? (i) `CH_(3)-CH_(2)-Br` , (ii) `H-overset(H)overset(|)C=O` (iii) `H-overset(H)overset(|)underset(H)underset(|)C-overset(H)overset(|)underset(H)underset(|)C-overset(H)overset(|)underset(H)underset(|)C-overset(H)overset(|)underset(H)underset(|)C-CequivC-H` |
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Answer» (i) Bromoethane (ii) Methanal (iii) Hexyne |
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| 86. |
Which of the following does not belong to the same homologous series?A. `CH_(4)`B. `C_(2)H_(6)`C. `C_(3)H_(8)`D. `C_(3)H_(6)`. |
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Answer» Correct Answer - D It is an alkene while the rest are all alkane molecules in nature. |
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| 87. |
Write the names of the following compounds. (a) `H-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-overset(O)overset(||)C-OH` , (b) `H-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-C-=C-H` (c ) `H-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-overset(H)overset(|)C=O` , (d) `H-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-OH` |
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Answer» (a) Pentane - e + oic acid = Pentanoic acid (because it contains five C atoms and one -COOH group). Pentane - e + yne = Pentyne (due to the presence of five carbon atoms along with a triple bond). (c ) Heptane - e + al = Heptanal (as it contains 7 carbon atoms and a -CHO group) (d) Pentane - e- + ol = Pentanol (as it contains 5 carbon atoms and one -OH group) |
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| 88. |
The hateroatoms present in `CH_(3)-O-CH_(2)-CH_(2)(Br)` are (i) oxygen (ii) carbon (iii) hydrogen (iv) bromineA. (i) and (ii)B. (ii) and (iii)C. (iii) and (iv)D. (i) and (iv) |
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Answer» Correct Answer - D both oxygen (O) and bromine (Br) are heteroatoms. Please remember that apart from C and H atoms, all other atoms present in an organic compound are hetero atoms. |
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| 89. |
Which of the following burns by producing a yellow luminous flame?A. natural gasB. cokeC. waxD. charcoal |
| Answer» Correct Answer - (c ) | |
| 90. |
The first member of alkene family isA. ethyneB. etheneC. propyneD. ethane |
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Answer» Correct Answer - B Ethene `(CH_(2)=CH_(2))` is the first member of alkene family. |
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| 91. |
The heteroatoms present in `CH_(3)-CH_(2)-O-CH_(2)-CH_(2)Cl` (i) oxygen, (ii) carbon (iii) hydrogen, (iv) chlorineA. (i) and (ii)B. (ii) and (iii)C. (iii) and (iv)D. (i) and (iv) |
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Answer» Correct Answer - D Atoms other than C and H, if present in organic compound, are called heteroatoms. |
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| 92. |
A compound C (molecular formula, `C_(2)H_(4)O_(2)`) reacts with Na metal to form a compounds R and evolves a gas which burns with a pop sound. Compound C on treatment with an alcohol A in the presence of an acid form a sweet smelling compound S (molecular formula, `C_(3)H_(6)O_(2))`. 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. |
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Answer» From the available information, it is evident that (i) Compound C with moleculr formula `C_(2)H_(4)O_(2)` is ethanoic acid `(CH_(3)COOH)` (ii) The compound R is sodium ethanoate and has formula `CH_(3)COONa` (iii) Since the compound S has only three carbon atoms `(C_(3)H_(6)O_(2))` and has been formed by the action of an alcohol on compound `C(C_(2)H_(4)O_(2))`, this means that the alcohol A has only one carbon atom. it is methanol `(CH_(3)OH)`. (iv) The compound S with a sweet smell is methyl ethanoate with formula `CH_(3)COOCH_(3)`. The chemical reactions involved are as follows: (a) `underset((C))(2CH_(3)COOH)+2Natounderset((R))(2CH_(3)COONa)+H_(2)` (b) `underset((C))(CH_(3)COOH)+underset((A))(CH_(3)OH)overset("conc. "H_(2)SO_(4))tounderset((S))(CH_(3)COOCH_(3))+H_(2)O` (c) `underset((C))(CH_(3)COOH)+NaOHtounderset((R))(CH_(3)COONa)+H_(2)O` (d) `underset((S))(CH_(3)COOCH_(3))+NaOHtounderset((R))(CH_(3)COONa)+underset((A))(CH_(3)OH)` |
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| 93. |
What are the essential constituents of all organic compound? |
| Answer» Carbon and hydrogen are the essential constituents of all organic compounds. However, carbon tetrachloride `(C Cl_(4))` is an exception. | |
| 94. |
What is the role of soap in cleansing of clothes? |
| Answer» Soap helps in forming a stable emulsion between oil drops carrying dirt particles and water. The emulsion is also known as micelle. | |
| 95. |
Which organic compound is added to make ethanol unfit for drinking purposes? What is the name of the mixture formed? |
| Answer» Methanol which is highly poisonous is added in small amount to ethanol in order to make it unfit for drinking purposes. The mixture is called methylated spirit or denatured alcohol. | |
| 96. |
Which of the following represents saponification reaction ?A. `CH_(3)COONa+NaOHoverset(CaO)toCH_(4)+Na_(2)CO_(3)`B. `CH_(3)COOH+C_(2)H_(5)OHoverset(H_(2)SO_(4))toCH_(3)COOC_(2)H_(5)+H_(2)O`C. `2CH_(3)COOH+2Nato2CH_(3)COONa+H_(2)`D. `CH_(3)COOC_(2)H_(5)+NaOHtoCH_(3)COONa+C_(2)H_(5)OH` |
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Answer» Correct Answer - D In saponification reaction, when an ester is heated with sodium hydroxide solution, ester gets hydrolysed (breaks down) to form the parent alcohol and sodium salt of carboxylic acid. |
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| 97. |
One of he following burns without producing a flame . This is :A. woodB. charcoalC. LPGD. candle |
| Answer» Correct Answer - (b) | |
| 98. |
The molecular formula of butane is `C_(4)H_(10)`. What is the formula of butene? |
| Answer» The formula of butene is `C_(4)H_(8)`. | |
| 99. |
How would you name the following compound? |
| Answer» This v compound is hydrocarbon which contains 6 carbons atoms in its molecuyle .The indicated by the suffiex yne . Now by combining hex and yne, the IUPAC name of the above compound becomes hexyne (hex + yne = hexyne). | |
| 100. |
Identify and name the functional groups present in the following compounds. (a) `H-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-OH` , (b) `H-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-overset(O)overset(||)C-OH` (c ) `H-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-overset(O)overset(||)C-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-H` , (d) `H-underset(H)underset(|)overset(H)overset(|)C-underset(H)underset(|)overset(H)overset(|)C-overset(H)overset(|)C=overset(H)overset(|)C-H` |
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Answer» (a) -OH (alcohol) , (b) `-underset(O)underset(||)C-OH` (carboxylic acid) (c ) `-underset(O)underset(||)C-` (ketone) , (d) -C=C- (alkene) |
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