The mass of one atom of element X is 4.48 × 10-23 g.
Relative atomic mass (ArA_rAr): Na = 23.0 Mg = 24.3 Al = 27.0 Si = 28.1
The Avogadro constant is 6.02 × 1023.
What is element X?
Sodium
Magnesium
Aluminium
Silicon
55 exam-style questions on OCR GCSE Chemistry 3.1 Introducing chemical reactions, covering 3.1.1 Writing formulae and balanced chemical equations, 3.1.2 Formulae of compounds from ions, and state symbols, 3.1.3 Conservation of mass and observed changes in mass, 3.1.4 Half equations and balanced ionic equations, 3.1.5 The mole and the Avogadro constant, and 3.1.6 Stoichiometry, limiting reactants and reacting masses. Each one has a worked solution and a mark scheme showing where the marks go.