SUMMARY
The volume of dry hydrogen gas at standard temperature and pressure (STP) can be calculated using the formula P1V1/T1 = P2V2/T2. In this discussion, a 32.0 mL sample of hydrogen collected at 20°C and 750.0 torr was adjusted for water vapor pressure, resulting in a dry pressure of 732.5 torr. The calculated volume at STP (0°C and 760 torr) is 31.3 mL, but the answer key indicates 28.7 mL, highlighting a common confusion between STP and standard ambient temperature and pressure (SATP), which is 25°C.
PREREQUISITES
- Understanding of gas laws, specifically the ideal gas law.
- Knowledge of vapor pressure calculations, particularly for water at different temperatures.
- Familiarity with standard temperature and pressure (STP) definitions.
- Basic algebra for manipulating equations involving pressure, volume, and temperature.
NEXT STEPS
- Research the differences between STP and SATP, including their applications in scientific calculations.
- Learn about the vapor pressure of water at various temperatures and its impact on gas volume calculations.
- Explore the ideal gas law and its applications in real-world scenarios.
- Practice solving gas law problems using different conditions and variables.
USEFUL FOR
Chemistry students, educators, and professionals involved in gas law calculations and thermodynamics will benefit from this discussion.