Lesson 2A.3

2A.3 Electronegativity and bond polarity Quiz: Pearson Edexcel Chemistry, Unit 2

20 questions

Written by Revision Ninja · Last reviewed 11 October 2026

In partnership with Revision Ninja

Lesson 2A.3, Electronegativity and bond polarity: 20 multiple choice questions for the Pearson Edexcel Chemistry (9CH0), Unit 2: Bonding and Structure, 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 electronegativity?

    • The ability of an atom to attract the bonding electrons in a covalent bond
    • The energy needed to remove an electron from an atom in the gaseous state, measured per mole of atoms
    • The mass of an atom compared with one-twelfth of the mass of a carbon-12 atom in the standard scale
    • The energy released when an atom in the gaseous state gains an electron to form a negative ion

  2. Which element is the most electronegative?

    • Nitrogen
    • Oxygen
    • Chlorine
    • Fluorine

  3. Which bond is most polar?

    • H-I
    • H-F
    • H-Cl
    • H-Br

  4. Which bond is non-polar?

    • Cl-Cl
    • N-H, a bond between nitrogen and hydrogen in which the nitrogen attracts the bonding electrons more
    • C-O, a bond between carbon and oxygen in which the oxygen attracts the bonding electrons more
    • H-Cl, a bond between hydrogen and chlorine in which the electrons are shared unequally

  5. Which pair of atoms has the largest electronegativity difference?

    • N and H
    • H and Cl
    • C and O
    • Na and F

  6. Why is the CO2 molecule non-polar, although each C=O bond is polar?

    • It is an ionic compound, so its charges are fixed in place and cannot produce a dipole across the molecule
    • Its two bond dipoles are linear and cancel out
    • Its bonds are all single bonds, so there is no unequal sharing of electrons between the carbon and oxygen
    • It has no lone pairs on the carbon atom, so the bonding electrons are shared exactly equally between the atoms

  7. Which molecule is polar?

    • CCl4, a tetrahedral molecule in which the four polar C-Cl bonds cancel out completely by symmetry
    • BF3, a trigonal planar molecule in which the three polar B-F bonds sum to zero by symmetry
    • CHCl3
    • CO2, a linear molecule in which the two polar C=O bonds point in opposite directions and cancel

  8. In a C-Cl bond, which atom carries the partial negative charge?

    • Carbon
    • Chlorine
    • Both atoms equally
    • Neither atom, because the bond is non-polar

  9. Which carbon-halogen bond is most polar?

    • C-I
    • C-Br
    • C-Cl
    • C-F

  10. Explain why CH3Cl is polar but CCl4 is not.

    • CCl4 has more polar bonds than CH3Cl, which makes the molecule more polar overall despite its symmetrical shape
    • Both are non-polar because they both contain a carbon atom bonded to several other atoms in a tetrahedral way
    • CH3Cl has no polar bonds at all, because the C-H bond is non-polar and the C-Cl bond cancels out in the molecule
    • CH3Cl has bonds of unequal polarity arranged asymmetrically, so its dipoles do not cancel; CCl4 is symmetrical so its dipoles cancel

  11. A molecule has polar bonds arranged symmetrically around its central atom. Which statement is true?

    • The molecule is polar because each of its individual bonds is polar, whatever the symmetry of the overall arrangement
    • The molecule is ionic because it contains polar bonds, which always transfer electrons between the atoms
    • The molecule has a net permanent dipole because the bonds together produce a single overall dipole in one direction
    • The molecule is non-polar because the bond dipoles cancel

  12. What is a polar covalent bond?

    • A bond formed by delocalised electrons in a metal, which move freely through a lattice of positive metal ions
    • A covalent bond in which the shared electrons are drawn unequally towards one atom because of an electronegativity difference
    • A bond formed between two identical atoms in which the two shared electrons are held equally by both nuclei
    • A bond in which electrons are completely transferred from one atom to another, leaving the two atoms as separate charged ions

  13. Which molecule has the most polar bonds: H2O, H2S or H2Se?

    • H2S
    • H2O
    • H2Se
    • H2Te

  14. Which molecule is non-polar, despite having polar bonds?

    • CS2
    • CO
    • NH3
    • SO2

  15. Predict whether BF3 is polar and justify your answer.

    • Non-polar, because it is trigonal planar and its three B-F bond dipoles cancel
    • Polar, because the fluorine lone pairs on each atom create a net dipole that points towards the boron atom
    • Non-polar, because boron has no lone pairs at all, so none of its bonds can carry any polarity whatsoever
    • Polar, because the B-F bonds are polar and the molecule is asymmetric, so the dipoles fail to cancel out fully

  16. Which statement about electronegativity across Period 2 is correct?

    • It stays the same across the period
    • It peaks at carbon and then falls
    • It decreases from lithium to fluorine
    • It increases from lithium to fluorine

  17. Explain why HCl is polar but Cl2 is not, using electronegativity.

    • Cl2 has more lone pairs on its atoms than HCl does, and these lone pairs stop its dipoles from cancelling
    • HCl has no shared electrons between its two atoms, so it cannot form a polar bond in the first place
    • Cl2 has a larger electronegativity difference than HCl, which is why the chlorine molecule forms polar bonds
    • H and Cl differ in electronegativity so the bond is polar, whereas the Cl-Cl bond shares electrons equally, giving no dipole

  18. A bond between X and Y has an electronegativity difference of 1.7. Which description is best?

    • Polar covalent, with substantial ionic character towards the ionic end of the continuum
    • Purely ionic, with complete transfer of electrons from one atom to the other in the bond between them
    • Metallic, with delocalised electrons that move freely between the two atoms and are shared across the bond
    • Non-polar covalent, with equal sharing of electrons, because the two atoms attract the bonding pair equally strongly

  19. Which of these bonds has the smallest electronegativity difference?

    • O-H
    • N-H
    • C-H
    • F-H

  20. Which element in Group 6 is the most electronegative?

    • Sulfur
    • Oxygen
    • Tellurium
    • Selenium

All Pearson Edexcel Chemistry quizzes