Lithium, sodium, and potassium are three alkali metals in Group 1 of the Periodic Table.
A small, equal-sized piece of each metal is added to a trough containing water. Complete the table by writing the correct metal (lithium, sodium, or potassium) next to each observation.
| Observation of reaction | Metal |
|---|---|
| Melts into a silvery ball, darts rapidly across the water surface, and ignites with a characteristic lilac flame | |
| Fizzes steadily on the water surface, gradually becoming smaller while keeping its solid shape | |
| Melts into a shiny, silvery droplet and fizzes vigorously while moving rapidly across the water surface without catching fire |
Give the name and chemical formula of the gaseous product formed when potassium reacts with water.
Name:
Formula:
Give the name and chemical formula of the alkaline compound formed when sodium reacts with water.
Name:
Formula:
Describe how you could use a chemical indicator to show that an alkaline solution is formed when lithium reacts with water. State the indicator used and the color change observed.
21 exam-style questions on Edexcel IGCSE Chemistry Group 1 (alkali metals) – lithium, sodium and potassium. Each one has a worked solution and a mark scheme showing where the marks go.