Layout of the periodic table
Layout of the periodic table

The periodic table is arranged by increasing atomic number, which is the number of protons in the nucleus. In a neutral atom, atomic number also equals the number of electrons.
Layout of the periodic table
Layout of the periodic table

The periodic table is arranged by increasing atomic number, which is the number of protons in the nucleus. In a neutral atom, atomic number also equals the number of electrons.
Step-by-step lessons covering AQA GCSE Combined Science The periodic table for Foundation and Higher tier. Each lesson works through exam-style questions.