Covalent bonding and simple molecules
Watch the whole lecture free
Make a free account to watch every lecture to the end: 3 worked examples, 6 practice questions, 2 real past-paper questions with the answers explained, the mistakes that lose marks, the full-marks tip, a one-card summary and a quick quiz.
That was the teaching part. The rest of this lecture is free with an account: 3 worked examples, 6 practice questions, 2 real past-paper questions with the answers explained, the mistakes that lose marks, the full-marks tip, a one-card summary and a quick quiz.
No password needed now: we email you a link to set one. Already have an account? Sign in, then come back to this page.
The teaching part (1 min) is free to watch. A free account opens the whole lecture: 3 worked examples, 6 practice questions, 2 real past-paper questions with the answers explained, the mistakes that lose marks, the full-marks tip, a one-card summary and a quick quiz.
What this lecture covers
- Atoms that share
- What is a covalent bond?
Read the transcript of the teaching part
Last time
Before we start: last time, in Comparing structures and properties, you learned these points. Here they are again on one card. Keep them in mind, because today builds on them.
Atoms that share
Water, oxygen, carbon dioxide and methane are all made of small molecules. In every one of them, the atoms are held together by sharing electrons. That is covalent bonding, and it explains why these substances are so different from salt.
What is a covalent bond?
A covalent bond is a pair of electrons shared between two atoms. It forms between non-metal atoms, such as hydrogen, oxygen, nitrogen and chlorine. Each atom gets a full outer shell by sharing, so no electrons are transferred. The bond is the electrostatic attraction between the shared pair and the two positive nuclei.
How often it comes up
How often Cambridge has asked each part, counted by ExamYard from every past paper in its question bank: Covalent bonding · Properties of simple molecular substances · Simple molecules and covalent bonds.
The whole chapter: Atoms, Elements and Compounds, Atoms, Elements and Compounds.
Chapter 2: Atoms, elements and compounds
- Atoms: protons, neutrons and electrons 6 min
- Isotopes and relative atomic mass 7 min
- Electronic configuration 5 min
- Ionic bonding 6 min
- Covalent bonding and simple molecules 6 min
- Giant covalent structures 6 min
- Metallic bonding 6 min
- Comparing structures and properties 7 min
Also for IGCSE Chemistry 0620
Which topics come up most in IGCSE Chemistry 0620 past papers, counted from every paper since 2004.