Based on the behavior of molecules in a mixture of gases, which statement best explains how the Ideal Gas Law applies to the sample shown?

• A. Each gas in the mixture behaves independently and contributes to the total pressure according to its own number of moles.
• B. The molecules of different gases in the mixture interact strongly, causing deviations from the Ideal Gas Law.
• C. The Ideal Gas Law cannot be used for mixtures of gases, only for pure gases.
• D. Only the gas with the largest molar mass determines the pressure of the mixture.

Answer: (A)

Verified step by step guidance

1. Understand that the Ideal Gas Law, given by the equation \(P V = n R T\), relates the pressure (\(P\)), volume (\(V\)), number of moles (\(n\)), gas constant (\(R\)), and temperature (\(T\)) for an ideal gas.
2. Recognize that in a mixture of gases, each gas behaves independently and exerts its own partial pressure, which depends on its own number of moles, volume, and temperature.
3. Recall Dalton's Law of Partial Pressures, which states that the total pressure of a gas mixture is the sum of the partial pressures of each individual gas: \(P_{total} = P_1 + P_2 + \dots + P_n\).
4. Since each gas follows the Ideal Gas Law individually, the partial pressure of each gas can be expressed as \(P_i = \frac{n_i R T}{V}\), where \(n_i\) is the number of moles of gas \(i\).
5. Therefore, the total pressure in the mixture is the sum of these individual pressures, showing that each gas contributes independently to the total pressure according to its own number of moles.