Hydrogen gas is used as a fuel in some buses. Hydrogen is an element that exists as molecules, H2\mathrm{H_{2}}H2.
State what is meant by a covalent bond.
Give the number of covalent bonds in a hydrogen molecule.
State what is meant by a molecule.
State the number of electrons in the outer shell of each hydrogen atom in a hydrogen molecule.
State what the number 2 in the formula H2\mathrm{H_{2}}H2 tells you about a hydrogen molecule.
Give the approximate size of a small molecule such as a hydrogen molecule. Choose from: 1 × 10-3 m, 1 × 10-6 m, 1 × 10-10 m, 1 × 10-15 m.
53 exam-style questions on Edexcel GCSE Chemistry 2.4 Covalent bonding, covering 2.4.1 Covalent bonding and simple molecules. Each one has a worked solution and a mark scheme showing where the marks go.