Some properties of four solids, P, Q, R and S, are shown in the table below.
| Property | Solid P | Solid Q | Solid R | Solid S |
|---|---|---|---|---|
| Colour of solid | Black | White | Grey | White |
| Observation when added to water | Insoluble; black solid remains | Dissolves easily to form a colourless solution | Insoluble; grey solid remains | Partially dissolves to form a slightly cloudy mixture |
| pH of mixture with water | 7 | 11 | 7 | 12 |
| Observation when dilute hydrochloric acid is added | Reacts to form a blue-green solution; no bubbles | Effervescence; solid disappears to form a colourless solution | Effervescence; solid disappears to form a colourless solution | Reacts to form a colourless solution; no bubbles |
The solids, in no particular order, are calcium hydroxide, copper(II) oxide, sodium carbonate, and zinc metal.
Identify solids P, Q, R and S, explaining how the information in the table supports the identification of each solid.
Practise Edexcel GCSE Chemistry Acids with exam-style questions for Foundation and Higher tier. 276 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.
