# How to Calculate the New Volume of Helium Gas at Increased Temperature and Pressure

## What will be the new volume of the helium gas when the temperature is increased to 425.0K and the pressure is increased to 3.50 atm?

Given a sample of helium with a volume of 3.20x10² mL at STP, how can we calculate the new volume as the temperature and pressure increase?

## Answer:

The new volume of the sample of helium gas as its temperature and pressure increases to the given values is 1.40×10² mL.

The Combined gas law combines Boyle's Law, Charles's Law, and Gay-Lussac's Law to calculate the behavior of gases under changing conditions. It states that the ratio of the product of volume and pressure to the absolute temperature of a gas is constant.

The formula for the Combined gas law is: P₁V₁/T₁ = P₂V₂/T₂

Given the initial volume of helium gas V₁ = 3.20 × 10² mL = 0.32 L and initial pressure P₁ = 1.0 atm at standard temperature and pressure (T₁ = 273.15 K).

With final pressure P₂ = 3.50 atm and final temperature T₂ = 425.0 K, we need to calculate the final volume V₂.

Using the formula, we find: V₂ = (1.0 atm × 0.32 L × 425.0 K) / (3.50 atm × 273.15 K) = 1.40×10² mL.

Therefore, the new volume of the sample of helium gas as its temperature and pressure increase to the given values is 1.40×10² mL.