Class 10 Science – Mock Test Paper Chapter: Carbon and Its Compounds
๐ Class 10 Science – Mock Test Paper
Chapter: Carbon and Its Compounds
Maximum Marks: 30
Time: 1½ hours
Section – A (1 × 5 = 5 marks)
- Write the molecular formula of propane.
- What is the functional group of alcohol?
- Name the product formed when ethanol is heated with excess concentrated H₂SO₄ at 443 K.
- State the reaction observed when acetic acid is added to NaHCO₃ solution.
- Write the structural formula of ethyne.
Section – B (2 × 3 = 6 marks)
- Why does carbon form compounds mainly by covalent bonding?
- Differentiate between soaps and detergents.
- Write the reaction of saponification and name the products formed.
Section – C (3 × 4 = 12 marks)
- Draw the electron dot structure of methane (CH₄).
- State three characteristics of a homologous series with an example.
- Explain the mechanism of cleaning action of soap with the help of a labeled diagram.
- Write chemical equations for the following reactions:
(i) Oxidation of ethanol
(ii) Esterification of ethanol with acetic acid
(iii) Reaction of ethanoic acid with NaOH
Section – D (5 × 1 = 5 marks)
- (a) What is hydrogenation reaction? Explain with an example and state its industrial application.
(b) Give two differences between saturated and unsaturated hydrocarbons.
✅ Marking Scheme (Suggested Answers)
Section A:
- C₃H₈
- –OH
- Ethene (C₂H₄)
- CO₂ gas evolves (effervescence)
- HC≡CH
Section B:
6. Carbon has 4 valence electrons → tetravalent → shares electrons → forms covalent bonds.
7. Soaps: Made from vegetable oils/fats, form scum in hard water.
Detergents: Made from petrochemicals, work in hard & soft water.
8. Ester + NaOH → Sodium salt of acid (soap) + Alcohol.
Section C:
9.
H
|
H–C–H
|
H
- Same functional group, same general formula, differ by –CH₂ group, similar chemical properties. Example: CH₄, C₂H₆, C₃H₈.
- Soap molecules form micelles → hydrophobic tail traps dirt, hydrophilic head remains in water → grease removed.
(i) C₂H₅OH + [O] → CH₃COOH + H₂O
(ii) CH₃COOH + C₂H₅OH → CH₃COOC₂H₅ + H₂O
(iii) CH₃COOH + NaOH → CH₃COONa + H₂O
Section D:
13. (a) Addition of hydrogen to unsaturated hydrocarbons in presence of Ni/Pd catalyst. Example: C₂H₄ + H₂ → C₂H₆.
Industrial use: Conversion of vegetable oil to ghee.
(b) Saturated: Single bonds, less reactive. Unsaturated: Double/triple bonds, more reactive.
Comments
Post a Comment