A student investigates an unknown metal, R. The student concludes that R is a Group 1 metal because it is shiny and conducts electricity.
| Observation or result | Finding |
|---|---|
| Appearance and electrical conductivity of R | R is shiny and conducts electricity |
| Density | R has a density of 8.9 g/cm3; potassium has a density of 0.86 g/cm3 |
| Reaction with cold water | R shows no visible reaction; potassium reacts vigorously and releases hydrogen |
| A compound of R dissolved in water | A blue solution forms |
| A second compound of R in a reaction | It speeds up the decomposition of hydrogen peroxide and is recovered unchanged afterwards |
Evaluate the student's conclusion. Use information from the table.
113 exam-style questions on OCR GCSE Chemistry 4.1 Predicting chemical reactions, covering 4.1.1 Properties and trends in Groups 1, 7 and 0, 4.1.2 Properties of the transition metals, 4.1.3 Reactivity predicted from position in the Periodic Table, and 4.1.4 Reactivity of metals and the reactivity series. Each one has a worked solution and a mark scheme showing where the marks go.