Potassium permanganate is a purple solid that is soluble in water.
A crystal of potassium permanganate is placed in a beaker containing water.
After a short time, the crystal becomes smaller and the liquid at the bottom of the beaker becomes purple.
Which statement explains this observation?
Choose your answer
the crystal condenses in the water
the crystal dissolves in the water
the crystal evaporates in the water
the crystal melts in the water
The beaker is left until there is no further change in the appearance of the liquid.
i) Which statement describes the final appearance of the liquid?
(1 mark)
| ☐ | A | all of the liquid is purple |
|---|---|---|
| ☐ | B | none of the liquid is purple |
| ☐ | C | only the bottom half of the liquid is purple |
| ☐ | D | only the top half of the liquid is purple |
ii) Which process causes this change in appearance?
(1 mark)
| ☐ | A | condensation |
|---|---|---|
| ☐ | B | crystallisation |
| ☐ | C | diffusion |
| ☐ | D | evaporation |
The formula of potassium permanganate is KMnO4.
How many different elements are there in potassium permanganate?
Choose your answer
3
4
6
7
