Question

A balloon contains 2500 mL of helium gas at 75 °C. What is the final volume, in mL of the gas when the temperature changes to 240 K, if pressure and amount of gas do not change?

Options:
A) 1700 mL
B) 3625 mL
C) 1724 mL
D) 3600 mL

Answer 1

Using Charles's Law, convert the initial temperature from Celsius to Kelvin, apply V1/T1 = V2/T2, and solve for V2 to get approximately 1724 mL, making option C the correct answer.

Step-by-step explanation:

To determine the final volume of helium gas when the temperature changes, you can use Charles's Law, which states that at constant pressure, the volume of a gas is directly proportional to its absolute temperature. The law can be described by the equation V1/T1 = V2/T2, where V1 is the initial volume, T1 is the initial temperature, V2 is the final volume, and T2 is the final temperature. Remember to convert all temperatures to Kelvin.

First, convert the initial temperature of 75 °C to Kelvin by adding 273.15 to get T1 = 348.15 K. Given that V1 = 2500 mL and T2 = 240 K, we can rearrange the equation to solve for V2: V2 = V1 * (T2/T1). Substituting the given values, V2 = 2500 mL * (240 K / 348.15 K), which yields V2 ≈ 1724 mL. Hence, option C is the correct answer.