Water, H2O\mathrm{H_{2}O}H2O, is made of small molecules. The atoms in a water molecule are held together by covalent bonds.
Oxygen has atomic number 8.
Give the electronic configuration of an oxygen atom.
State how many more electrons an oxygen atom needs to fill its outer shell.
Give the number of covalent bonds in a water molecule.
State the number of pairs of electrons in the outer shell of the oxygen atom in water that are not used in bonding.
A student writes: "In a water molecule, the oxygen atom gives electrons to the hydrogen atoms." Explain why the student is wrong.
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.