Complete the following table for air and then for hydrogen:
| Pressure | Volume |
|---|---|
| Air | |
|---|---|
| Pressure (hPa) | Volume (ml) |
| 30,0 | 14,4 |
| 25,2 | 17,0 |
| 20,1 | 21,4 |
| 15,2 | 27,0 |
| Dihydrogène | |
|---|---|
| Pression (hPa) | Volume (ml) |
| 30,0 | 14,3 |
| 24,9 | 17,2 |
| 20,1 | 20,6 |
| 15,0 | 26,3 |
Try to calculate the sum, difference, quotient, product.. of these numbers. Try to find a law !
| Air | ||
|---|---|---|
| Pressure (hPa) | Volume (ml) | Pressure · Volume |
| 30,0 | 14,4 | 432 |
| 25,2 | 17,0 | 429 |
| 20,1 | 21,4 | 430 |
| 15,2 | 27,0 | 410 |
| Dihydrogène | ||
|---|---|---|
| Pressure (hPa) | Volume (ml) | Pressure · Volume |
| 30,0 | 14,3 | 429 |
| 24,9 | 17,2 | 428 |
| 20,1 | 20,6 | 414 |
| 15,0 | 26,3 | 394 |
We see that for a given quantity of gas we have approximately:
Pressure · Volume = Constant (Law of Boyle-Mariotte)
What restrictions?
1) A fixed amount of gas (the cylinder is air-tight) 2) A fixed temperature.