CIE A Level Chemistry
CIE A Level Chemistry Chemical Bonding Exam Questions
Free CIE A Level Chemistry exam questions for Chemical Bonding, with a mark scheme for every pack. Covers electronegativity, ionic, covalent, coordinate and metallic bonding, shapes of molecules, sigma and pi bonds, hybridisation and intermolecular forces.
Chemical Bonding exam questions
1 question pack of real past exam questions, each with its mark scheme. Do not stop after a few: answer as many as you can without notes, then mark every answer with the mark scheme. The more questions you do, the more quickly you will spot how examiners ask about each idea.
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A-Level Chemistry Flashcards for 2027 Onwards
Every answer is written in mark scheme wording, so you learn exactly what examiners give marks for. Then test yourself with the questions on this page.
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About CIE A Level Chemistry Chemical Bonding
Chemical bonding explains how particles are held together and why substances have the properties they do. In Cambridge International 9701 you need to describe ionic, covalent, coordinate (dative) and metallic bonding, use electronegativity to judge bond polarity, and predict molecular shapes and bond angles using electron pair repulsion. The syllabus also asks you to describe sigma and pi bonds and sp, sp2 and sp3 hybridisation, which links directly to alkenes and benzene in organic chemistry. Intermolecular forces, including hydrogen bonding and van der Waals forces, explain boiling points and solubility. This AS topic is heavily tested through dot-and-cross diagrams, shape predictions and explanations of physical properties.
What you need to know
- Electronegativity The power of an atom to attract the bonding pair of electrons in a covalent bond. It increases across a period and up a group, and a large difference between bonded atoms produces a polar bond or ionic bonding.
- Ionic, covalent and coordinate bonds Ionic bonding is electrostatic attraction between oppositely charged ions. A covalent bond is a shared pair of electrons, and in a coordinate bond both electrons come from one atom, as in NH4+ and Al2Cl6.
- Shapes of molecules Electron pairs repel to be as far apart as possible, and lone pairs repel more than bonding pairs. Learn linear (180), trigonal planar (120), tetrahedral (109.5), pyramidal (107), non-linear (104.5), trigonal bipyramidal (90 and 120) and octahedral (90).
- Sigma and pi bonds and hybridisation A sigma bond forms from direct end-on overlap of orbitals, and a pi bond from sideways overlap of p orbitals above and below the bond axis. Carbon in alkanes is sp3, in alkenes sp2 and in ethyne sp.
- Intermolecular forces Instantaneous dipole-induced dipole forces exist between all molecules and increase with number of electrons. Permanent dipole-permanent dipole forces occur between polar molecules. Hydrogen bonds form between H attached to N, O or F and a lone pair on N, O or F.
- Metallic bonding Electrostatic attraction between positive metal ions and delocalised electrons. It explains electrical conductivity, malleability and high melting points.
- Bond energy and length Bond energy is the energy needed to break one mole of a particular covalent bond in gaseous molecules. Shorter bonds are generally stronger, and multiple bonds are shorter than single bonds between the same atoms.
Common mistakes in Chemical Bonding
- Saying hydrogen bonds form between molecules of HCl; Cl is not electronegative enough, hydrogen bonding requires H bonded to N, O or F.
- Breaking covalent bonds when explaining the boiling point of a simple molecular substance; only intermolecular forces are overcome.
- Giving the bond angle in water as 109.5 degrees; two lone pairs reduce it to about 104.5 degrees.
- Drawing a pi bond as a second sigma bond; it is formed by sideways overlap of p orbitals and lies above and below the plane.
- Assuming any molecule with polar bonds is polar; symmetrical molecules such as CO2 and CCl4 have no overall dipole.
Try three Chemical Bonding exam-style questions
1. Predict the shape and bond angle of an ammonia molecule and explain your answer. (3 marks)
Show the mark scheme answer
Pyramidal; about 107 degrees; three bonding pairs and one lone pair; lone pair repels more strongly than bonding pairs so angle is reduced from 109.5.
2. Explain why water has a much higher boiling point than hydrogen sulfide. (3 marks)
Show the mark scheme answer
Water forms hydrogen bonds between molecules; H2S has only van der Waals forces (permanent dipole and instantaneous dipole forces); hydrogen bonds are stronger so more energy is needed to separate water molecules.
3. Describe the bonding in an ethene molecule in terms of orbital overlap. (3 marks)
Show the mark scheme answer
Each carbon is sp2 hybridised; sigma bonds form by end-on overlap between C and C and between C and H; pi bond forms by sideways overlap of the unhybridised p orbitals on each carbon, above and below the plane.
Chemical Bonding FAQs
What does Cambridge AS & A Level Chemistry Chemical bonding cover?
It covers electronegativity, ionic, covalent, coordinate and metallic bonding, molecular shapes, sigma and pi bonds, hybridisation and intermolecular forces.
How do I revise shapes of molecules?
Count bonding pairs and lone pairs around the central atom, then match to the standard shapes and angles; practise with ions such as NH4+, SF6 and ClF3 as well as neutral molecules.
Which intermolecular forces do I need to know?
Instantaneous dipole-induced dipole forces, permanent dipole-permanent dipole forces and hydrogen bonding, with examples of how each affects boiling point.
