A chemist tests a firework powder using flame emission spectroscopy. The table shows the results and a set of reference data.
| Substance | Wavelengths of lines (nm) |
|---|---|
| Lithium ions | 610, 671 |
| Sodium ions | 589 |
| Copper(II) ions | 511, 515, 522 |
| Firework powder | 461, 610, 671 |
What can the chemist conclude about the firework powder?
It contains lithium ions only.
It contains lithium ions and copper(II) ions.
It contains lithium ions and a metal ion not in the table.
It contains none of the metal ions in the table.
52 exam-style questions on OCR GCSE Chemistry 4.2 Identifying the products of chemical reactions, covering 4.2.1 Tests to identify gases, 4.2.2 Tests for aqueous ions and flame tests, and 4.2.3 Instrumental methods of analysis. Each one has a worked solution and a mark scheme showing where the marks go.