STUDENT SPACE · TOPIC 3
Gas volumes at room conditions
Use molar gas volume and gas ratios, including a purity calculation.
The essentials
- At room temperature and pressure, 1 mol of gas occupies 24 dm³.
- Use 24 with dm³, or 24 000 with cm³.
- 0.960 dm³ CO₂ at RTP corresponds to 0.960/24 = 0.0400 mol.
- Its mass is 0.0400 × 44 = 1.76 g.
Key vocabulary
| English | Chinese |
|---|---|
| molar gas volume | 气体摩尔体积 |
| room temperature and pressure | 室温和常压 |
| volume ratio | 体积比 |
Quick practice
A student calculates 480 ÷ 24 = 20 mol for 480 cm³ gas at RTP. Correct the calculation.
Need a hint?
Use the relationships above and check particle ratios and units.
Check your reasoning after trying
480/24 000 = 0.0200 mol, or 0.480/24 = 0.0200 mol.
Use Lesson 3 in your worksheet for written practice. Your teacher will discuss those answers in class.