Method
- Carefully measure 100 cm3 of hydrochloric acid using the measuring cylinder and place it in the beaker.
- Add 0.5g of the first test metal – magnesium – to the acid in the beaker.
- Start the stopwatch.
- Record the time it takes for the gas to stop being produced and for the metal to disappear.
- Repeat these steps for the other test metals – zinc and iron.
| Metal | Time taken to react (s) |
| Magnesium | â ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Ä |
| Zinc | â ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Ä⠀⠀ |
| Iron | â ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Ä⠀⠀ |
| Metal | Magnesium |
|---|---|
| Time taken to react (s) | â ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Ä |
| Metal | Zinc |
|---|---|
| Time taken to react (s) | â ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Ä⠀⠀ |
| Metal | Iron |
|---|---|
| Time taken to react (s) | â ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Äâ ¶Ä⠀⠀ |
To make the investigation more reliable each metal could be tested again and an average of the two times calculated.
This investigation could also be carried out by timing how long the reaction takes to produce a certain volume of gas.
The gas could be collected in a gas syringe.
To make this investigation a fair test, the metal should be the same mass and in the same form, e.g. granules or powdered.