Carbon And Its Compounds Book Back Questions 10th Science Lesson 11

10th Science Lesson 11

11] Carbon And Its Compounds

Book Back Questions with Answer and Do You Know Box Content

Do You Know?

Yeast and Fermentation: Yeasts are single – celled microorganisms, belonging to the class of fungi. The enzymes present in yeasts catalyse many complex organic reactions. Fermentation is conversion of complex organic molecules into simpler molecules by the action of enzymes. E.g. Curdling of milk.

Why ordinary soap is not suitable for using with hard water?

Ordinary soaps when treated with hard water, precipitate as salts of calcium and magnesium. They appear at the surface of the cloth as sticky grey scum. Thus, the soaps cannot be used conveniently in hard water.

Have you noticed the term “TFM” in soap: TFM means TOTAL FATTY MATTER. It is the one of the important factors to be considered to assess the quality of soap. A soap, which has higher TFM, is a good bathing soap.

Choose the best answers:

1. The molecular formula of an open chain organic compounds is C₃H₆. The class of the compound is

(a) Alkane

(b) Alkene

(c) Alkyne

(d) Alcohol

2. The IUPAC name of an organic compound is 3-Methyl butan-1-ol. What type compound it is?

(a) Aldehyde

(b) Carboxylic acid

(c) Ketone

(d) Alcohol

3. The secondary suffix used in IUPAC nomenclature of an aldehyde is _____________

(a) –ol

(b) –oic acid

(c) –al

(d) –one

4. Which of the following pairs can be the successive members of a homologous series?

(a) C₃H₈ and C₄H₁₀

(b) C₂H₂ and C₂H₄

(c) CH₄ and C₃H₆

(d) C₂H₅OH and C₄H₈OH

5. C₂H₅OH + 3 O₂🡪 2 CO₂ + 3 H₂O is a

(a) Reduction of ethanol

(b) Combustion of ethanol

(c) Oxidation of ethanoic acid

(d) Oxidation of ethanol

6. Rectified spirit is an aqueous solution which contains about _____________ of ethanol.

(a) 95.5%

(b) 75.5%

(c) 55.5%

(d) 45.5%

7. Which of the following are used as anaesthetics?

(a) Carboxylic acids

(b) Ethers

(c) Esters

(d) Aldehydes

8. TFM in soaps represents _____________ content in soap.

(a) Mineral

(b) Vitamin

(c) Fatty acid

(d) Carbohydrate

9. Which of the following statements is wrong about detergents?

(a) It is a sodium salt of long chain fatty acids

(b) It is sodium salts of sulphonic acids

(c) The ionic part in a detergent is –SO₃^–Na⁺

(d) It is effective even in hard water

Fill in the blanks:

1. An atom or a group of atoms which is responsible for chemical characteristics of an organic compound is called _______________

1. Nominal Group
2. Functional Group
3. Molecular Group
4. All the above

2. The general molecular formula of alkynes is _________________

1. C_nH_2n-2
2. C_nH_2n-1
3. C_nH_2n-3
4. C_nH_2n-4

3. In IUPAC name, the carbon skeleton of a compound is represented by ______________ (root word/prefix/suffix).

1. Stem Word
2. Molecular Word
3. Cellular Word
4. Root Word

4. (Saturated/Unsaturated) _______________ compounds decolourize bromine water.

5. Dehydration of ethanol by conc. Sulphuric acid forms ___________ (ethane/ethane).

6. 100% pure ethanol is called ____________

1. Pure alcohol
2. Absolute alcohol
3. Pure ethanol
4. Absolute ethanol

7. Ethanoic acid turns ___________ litmus to ______________

1. Red, blue
2. Red, Colourless
3. Blue, Red
4. Blue, Colourless

8. The alkaline hydrolysis of fatty acids is termed as ______________

1. Saponification
2. Alkalysis
3. Hydronification
4. None of the above

9. Biodegradable detergents are made of ______________ (branched/straight) chain hydrocarbons.

Match the following:

1. Functional group –OH – Benzene

2. Heterocyclic – Potassium stearate

3. Unsaturated – Alcohol

4. Soap – Furan

5. Carbocyclic – Ethene

Consider the statements given below and choose the correct option:

Answer the following questions using the data given below:

i) A and R are correct, R explains the A.

ii) A is correct, R is wrong.

iii) A is wrong, R is correct

iv) A and R are correct, R doesn’t explain A.

1. Assertion: Detergents are more effective cleansing agents than soaps in hard water.

Reason: Calcium and magnesium salts of detergents are water soluble.

2. Assertion: Alkanes are saturated hydrocarbons.

Reason: Hydrocarbons consist of covalent bonds.

Answers:

Choose the best answer:

1.Alkene 2. Alcohol 3. –al 4. C₃H₈ and C₄H₁₀ 5. Combustion of ethanol 6. 95.5% 7.

1. Ethers 8. Fatty Acid

9. It is a sodium salt of long chain fatty acids.

Fill in the blanks:

1. Functional group
2. C_nH_2n-2
3. root word
4. Unsaturated
5. Ethane
6. absolute alcohol
7. Blue, red
8. Saponification
9. straight

Match the following:

1. Alcohol 2. Furan 3. Ethene 4. Potassium sterate 5. Benzene

True or False:

1. A and R are correct, R explains the A.
2. A and R are correct, R doesn’t explain A.