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Year 10 Science — Carbon and its compounds

Explain why carbon shares electrons rather than trading them, tell a saturated compound from an unsaturated one, work along a homologous series, and name what soap does to oily dirt.

Name: ________________________

  1. 1.Sort each compound by whether it carries a double or triple bond between carbon atoms.

    Groups: Saturated · Unsaturated

    • Methane
    • Ethyne
    • Ethane
    • Propene
    • Cyclohexane
    • Ethene

  2. 2.Methane and chlorine are left together in sunlight, and one hydrogen of the methane is replaced by a chlorine atom. What kind of reaction is this?

    • a) An esterification reaction
    • b) An oxidation reaction
    • c) An addition reaction
    • d) A substitution reaction

  3. 3.Soap makes very little foam in water from a hand-pump, and leaves a curdy solid behind. Why?

    • a) It reacts with the calcium and magnesium salts that make the water hard
    • b) Hard water already holds detergent
    • c) The water is too cold for the soap to dissolve
    • d) The soap has been oxidised by the air

  4. 4.Match each ending used in a compound's name to the class of compound it marks.

    • Suffix -ol
    • Suffix -al
    • Suffix -one
    • Suffix -oic acid
    • Suffix -yne
    • Alcohol
    • Ketone
    • Alkyne
    • Carboxylic acid
    • Aldehyde

  5. 5.A gas stove burns with a yellow flame and blackens the bottom of the pan. What has gone wrong?

    • a) The pan is too close to the flame
    • b) The gas is being fed in too slowly
    • c) The air holes are blocked, so the fuel is burning incompletely
    • d) The fuel is unsaturated and cannot burn cleanly

  6. 6.Why does carbon share electrons instead of gaining or losing four of them?

    • a) Carbon atoms are too large to hold a charge
    • b) Carbon has no electrons in its outermost shell to give away
    • c) Six protons could neither hold ten electrons nor be stripped of four without great cost
    • d) Carbon already has a full outermost shell

  7. 7.An unsaturated hydrocarbon is warmed with hydrogen over a palladium catalyst. What comes out?

    • a) A haloalkane
    • b) A saturated hydrocarbon
    • c) An ester
    • d) A carboxylic acid

  8. 8.How many different carbon skeletons can be drawn for the formula C₄H₁₀?

    • a) Four
    • b) One
    • c) Three
    • d) Two

Answer key — Year 10 Science — Carbon and its compounds

  1. 1. Methane → Saturated; Ethane → Saturated; Cyclohexane → Saturated; Ethene → Unsaturated; Ethyne → Unsaturated; Propene → Unsaturated
  2. 2. d) A substitution reaction
  3. 3. a) It reacts with the calcium and magnesium salts that make the water hard
  4. 4. Suffix -ol → Alcohol; Suffix -al → Aldehyde; Suffix -one → Ketone; Suffix -oic acid → Carboxylic acid; Suffix -yne → Alkyne
  5. 5. c) The air holes are blocked, so the fuel is burning incompletely
  6. 6. c) Six protons could neither hold ten electrons nor be stripped of four without great cost
  7. 7. b) A saturated hydrocarbon
  8. 8. d) Two