- The problem involves applying Charles's Law, which states that for a given amount of gas at constant pressure, the volume is directly proportional to its absolute temperature (in Kelvin). The formula is V₁/T₁ = V₂/T₂.
- First, convert the initial temperature from Celsius to Kelvin: T₁ = 68.8°C + 273.15 = 341.95 K.
- Convert the final temperature from Celsius to Kelvin: T₂ = -30.9°C + 273.15 = 242.25 K.
- Use the formula V₂ = V₁ × (T₂ / T₁).
- Substitute the values: V₂ = 6.98 dm³ × (242.25 K / 341.95 K).
- Calculate the result: V₂ ≈ 6.98 × 0.7084 ≈ 4.94 dm³.
- The final volume of the hydrogen gas at -30.9°C is approximately 4.94 dm³.
Parent Tip: Review the logic above to help your child master the concept of gas laws worksheet answers.