Brass is an alloy of copper and zinc. Brass is harder than pure copper. Which statement explains why brass is harder than pure copper?
The zinc atoms fill the gaps and make the copper atoms smaller
The different sized atoms make the metallic bonds much stronger
The zinc atoms remove the delocalised electrons from the structure
The different sized atoms stop the layers sliding over each other
42 exam-style questions on AQA GCSE Chemistry 2.2 How bonding and structure are related to the properties of substances, covering 2.2.1a The three states of matter, 2.2.1b Limitations of the simple particle model, 2.2.2 State symbols in chemical equations, 2.2.3 Properties of ionic compounds, 2.2.4 Properties of small molecules, 2.2.5 Polymers, 2.2.6 Giant covalent structures, 2.2.7 Properties of metals and alloys, and 2.2.8 Metals as conductors. Each one has a worked solution and a mark scheme showing where the marks go.