Lesson 3.3.4.1

3.3.4.1 Structure, bonding and reactivity Quiz: AQA Chemistry, Unit 3

20 questions

Written by Revision Ninja · Last reviewed 11 October 2026

In partnership with Revision Ninja

Lesson 3.3.4.1, Structure, bonding and reactivity: 20 multiple choice questions for the AQA Chemistry (7405), Unit 3: Organic chemistry, written with Revision Ninja.

Host it live on the board and students join with a game code on their own devices, or revise alone with Free Play. The answers are revealed in the game.

Host this setFree Play

The 20 questions

  1. What is the general formula of alkenes with one C=C double bond?

    • CnH2n-2
    • CnH2n+2
    • CnH2n+1OH
    • CnH2n

  2. What type of bonding is present in the C=C double bond of an alkene?

    • One ionic bond and one covalent bond
    • One sigma bond and one pi bond
    • Two pi bonds only
    • Two sigma bonds only

  3. Why is the C=C double bond a centre of high electron density?

    • The C=C bond is ionic
    • The sigma bond contains no electrons
    • The double bond is always filled with hydrogen
    • The pi electron cloud lies above and below the bond, making it attractive to electrophiles

  4. What is the bond angle around each carbon in a C=C double bond?

    • About 109.5 degrees
    • About 90 degrees
    • About 120 degrees
    • About 180 degrees

  5. Why are alkenes described as unsaturated hydrocarbons?

    • They are always ionic salts
    • They contain only single bonds and no hydrogen
    • They are saturated with oxygen
    • They contain a C=C double bond and so can add other atoms across it

  6. Which compound is the simplest alkene?

    • Propane
    • Methane
    • Ethene
    • Ethane

  7. Which test would show that an organic compound is unsaturated?

    • Adding silver nitrate to form a white precipitate
    • Adding sodium hydroxide to form a blue precipitate
    • A flame test with a green flame
    • Decolourisation of bromine water

  8. What is the shape of the ethene molecule around each carbon?

    • Linear
    • Pyramidal
    • Tetrahedral
    • Trigonal planar

  9. Why is the C=C bond more reactive than a C-C bond?

    • The sigma bond is weaker than the pi bond
    • The C=C bond is ionic
    • The pi bond is weaker and more exposed to attack, so it breaks more easily
    • The C=C bond has no electrons

  10. Which molecule has a C=C double bond?

    • Propane
    • Methanol
    • Ethanoic acid
    • Propene

  11. What is the bond enthalpy trend of C=C compared with C-C?

    • The C=C bond is stronger overall but the pi part is weaker
    • The C=C bond and C-C bond have identical strengths
    • The C=C bond is weaker than the C-C bond in every case
    • The C=C bond is ionic while C-C is covalent

  12. Which of these compounds contains a C=C double bond with two different groups on each carbon?

    • Ethanol
    • Propane
    • But-2-ene
    • Ethene

  13. How many sigma and pi bonds are present in ethene, C2H4?

    • 6 sigma and 0 pi
    • 3 sigma and 1 pi
    • 4 sigma and 2 pi
    • 5 sigma and 1 pi

  14. What is the electron pair geometry around each carbon in ethene?

    • Five electron pairs arranged trigonal bipyramidal
    • Two electron pairs arranged linear
    • Four electron pairs arranged tetrahedral
    • Three electron pairs arranged trigonal planar

  15. Which property makes alkenes useful as starting materials in industry?

    • They are always solid at room temperature
    • They contain only ionic bonds
    • They are unreactive and therefore stable for storage
    • Their C=C bond is reactive towards electrophiles and other reagents

  16. Why are the electrons in the pi bond of an alkene more available for attack than in the sigma bond?

    • They lie above and below the molecular plane and are less tightly held
    • They are in the nucleus of the carbon atom
    • They are part of an ionic bond
    • They lie along the bond axis between the two atoms

  17. Which description best explains why ethene is planar?

    • Each carbon has two bonding regions only
    • The molecule has a lone pair on each carbon
    • Each carbon has three bonding regions arranged at 120 degrees in one plane
    • Each carbon has four bonding regions arranged tetrahedrally

  18. Explain why alkenes readily undergo addition reactions rather than substitution reactions.

    • The C=C bond is too strong to break
    • The pi bond is weaker than the sigma bond, so the double bond opens up to add atoms across it
    • Alkenes contain no electrons available for reaction
    • Alkenes react only by removing hydrogen atoms

  19. Explain why the C=C bond in ethene is shorter than the C-C bond in ethane.

    • The C=C bond contains fewer electrons than the C-C bond
    • The double bond is ionic and so shorter
    • The double bond holds more shared electron pairs, pulling the carbon nuclei closer together
    • Ethene has longer carbon chains than ethane

  20. Which feature of a double bond gives it a high electron density region?

    • The pi electron cloud above and below the bond axis
    • The hydrogen atoms bonded to carbon
    • The sigma bond in the molecular axis only
    • The lone pairs on carbon atoms

All AQA Chemistry quizzes