A school technician has samples of two unidentified substances, X and Y.
The technician carries out a series of tests on X and on an aqueous solution of Y. The tests and results are shown in the table below:
| Test | Result |
|---|---|
| Add solid X to water and shake | The white solid dissolves to form a colourless solution |
| Add universal indicator to the solution of X | The indicator turns blue |
| Flame test with solid X | A red flame is produced |
| Appearance of solution of Y | Colourless liquid |
| Add universal indicator to solution of Y | The indicator turns orange |
| Add a small piece of magnesium ribbon to solution of Y | Bubbles of gas are released and the magnesium eventually disappears |
| Add a spatula measure of solid X to solution of Y | Bubbles of gas are released that turn limewater cloudy, and solid X disappears |
Identify X and Y, using all of the data in the table. Fully explain your reasoning by linking each test to your deductions.
Practise Edexcel GCSE Chemistry Qualitative analysis: tests for ions with exam-style questions for Foundation and Higher tier. 127 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
