Vardaan Learning Institute

Topic: Carbon and its Compounds

Class: 10 (Science) Type: Bonus Practice Paper Max. Marks: 50
Name:
Date:
SECTION A: OBJECTIVE TYPE QUESTIONS (1 Mark Each)
1. The number of isomers of pentane is:
  1. 2
  2. 3
  3. 4
  4. 5
2. Which of the following does not belong to the same homologous series?
  1. $CH_4$
  2. $C_2H_6$
  3. $C_3H_8$
  4. $C_4H_8$
3. The name of the functional group present in propanone is:
  1. Alcohol
  2. Carboxylic Acid
  3. Ketone
  4. Aldehyde
4. Which of the following statements is not correct about carbon compounds?
  1. They differ by $-CH_2$ unit in homologous series.
  2. They have low melting and boiling points.
  3. They are generally poor conductors of electricity.
  4. They have strong forces of attraction between the molecules.
5. Ethanol reacts with sodium to form two products, these are:
  1. Sodium ethanoate and hydrogen
  2. Sodium ethanoate and oxygen
  3. Sodium ethoxide and hydrogen
  4. Sodium ethoxide and oxygen
6. Carbon forms four covalent bonds by sharing its four valence electrons with four univalent atoms, e.g. hydrogen. After the formation of four bonds, carbon attains the electronic configuration of:
  1. Helium
  2. Neon
  3. Argon
  4. Krypton
7. The soap molecule has a:
  1. Hydrophilic head and a hydrophobic tail
  2. Hydrophobic head and a hydrophilic tail
  3. Hydrophobic head and a hydrophobic tail
  4. Hydrophilic head and a hydrophilic tail
8. Which of the following is an example of an addition reaction?
  1. $CH_4 + Cl_2 \rightarrow CH_3Cl + HCl$
  2. $CH_2=CH_2 + H_2 \rightarrow CH_3-CH_3$
  3. $CH_3COOH + Ethanol \rightarrow Ester$
  4. $CH_3COOH + NaOH \rightarrow CH_3COONa + H_2O$
9. When ethanoic acid is treated with aqueous sodium bicarbonate solution, the gas evolved is:
  1. $H_2$
  2. $CO_2$
  3. $O_2$
  4. $NH_3$
10. Oils on treating with hydrogen in the presence of palladium or nickel catalyst form fats. This is an example of:
  1. Addition reaction
  2. Substitution reaction
  3. Displacement reaction
  4. Oxidation reaction
Directions (Q11-Q14): In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is not the correct explanation of A.
  3. A is true but R is false.
  4. A is false but R is true.
11. Assertion (A): Carbon forms covalent compounds.
Reason (R): Carbon has 4 valence electrons and it can neither gain nor lose 4 electrons easily.
12. Assertion (A): Vegetable oils are healthy for cooking.
Reason (R): Vegetable oils contain long chains of saturated carbons.
13. Assertion (A): Diamond and Graphite are chemical analogues.
Reason (R): Both are allotropes of Carbon.
14. Assertion (A): Ethanol is used in making tinctures and cough syrups.
Reason (R): Ethanol is a good solvent.
SECTION B: SHORT ANSWER QUESTIONS (3 Marks Each)
15. (i) Write the electron-dot structures for (a) Methane ($CH_4$) and (b) Carbon dioxide ($CO_2$).
(ii) What is catenation? Explain why carbon shows this property to maximum extent.
16. (i) Define Homologous Series.
(ii) State any two characteristics of a homologous series.
(iii) Write the name and formula of the first member of the alkyne series.
17. (i) What are oxidising agents?
(ii) Name two oxidising agents which can oxidise Ethanol to Ethanoic acid.
(iii) Write the chemical equation for the oxidation of ethanol.
18. Draw the structures for the following compounds:
(i) Ethanoic acid
(ii) Bromopentane
(iii) Butanone
(iv) Hexanal
19. Give a chemical test to distinguish between:
(i) Ethanol and Ethanoic acid
(ii) Soaps and Detergents
20. (i) Write the general formula of Alkanes, Alkenes and Alkynes.
(ii) Explain with chemical equation, what happens when methane burns in oxygen.
SECTION C: LONG ANSWER QUESTIONS (5 Marks Each)
21. (i) Differentiate between Soaps and Detergents.
(ii) Explain the mechanism of cleaning action of soap with the help of a diagram (Micelle formation - student to draw).
(iii) Why do soaps not form lather with hard water?
22. (i) What is meant by Esterification reaction? Write the chemical equation.
(ii) How can an ester be converted back into alcohol and carboxylic acid? Name the reaction.
(iii) Give an important use of esters.
SECTION D: CASE STUDY (4 Marks)
23. Read the following text and answer the questions:
Carbon has the unique ability to form bonds with other atoms of carbon, giving rise to large molecules. This property is called catenation. These compounds may have long chains of carbon, branched chains of carbon or even carbon atoms arranged in rings. In addition, carbon atoms may be linked by single, double or triple bonds. Compounds of carbon, which are linked by only single bonds between the carbon atoms are called saturated compounds. Compounds of carbon having double or triple bonds between their carbon atoms are called unsaturated compounds.

(i) What is the general formula for Alkenes? (1 Mark)
(ii) Which allotrope of carbon is used as a lubricant? (1 Mark)
(iii) Draw the structure of Cyclohexane. (2 Marks)
24. Read the following text and answer the questions:
Two carbon compounds X and Y have the molecular formula $C_3H_6$ and $C_4H_{10}$ respectively. Which one of the two is most likely to show addition reaction? Justify your answer. Also give the chemical equation to explain the process of addition reaction in this case. (4 Marks)
"All the best!"