Theory (10 m)
A student is given two substances, P and Q. Substance P has a simple molecular structure, while substance Q has a giant ionic structure.
Explain how you would determine the formula of each substance and describe the differences between their particles, arrangement and chemical formula.
In your answer, include:
(a) The meaning of empirical formula and molecular formula. [2 marks]
(b) Explain how an empirical formula can be obtained from the relative masses of elements in a compound. [3 marks]
(c) Explain the difference between an empirical formula and molecular formula, with an example. [2 marks]
(d) Explain why the formula of an ionic compound represents the simplest ratio of ions rather than the number of molecules present. [3 marks]
September 8, 2026 1.3K 3 7
