Question

The statement, the total pressure of a mixture of ideal gases is the sum of partial pressures, is called as

• A. Boyle's law
• B. Charles' law
• C. Dalton's law
• D. Perfect gas law
• E. Law of equipartition

Hint:

For a mixture of ideal gases, remember: \[ P_{\text{total}}=\sum P_{\text{partial}} \] This is Dalton’s law of partial pressures.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
This is a definitional question asking to identify the specific gas law that describes the total pressure of a mixture of gases.
Step 2: Detailed Explanation:
Let's review the gas laws listed in the options:

(A) Boyle's law: States that for a fixed amount of gas at constant temperature, the pressure and volume are inversely proportional (\(P \propto 1/V\)). It deals with a single gas, not a mixture.

(B) Charles' law: States that for a fixed amount of gas at constant pressure, the volume is directly proportional to the absolute temperature (\(V \propto T\)). It also deals with a single gas.

(C) Dalton's law: Specifically, Dalton's Law of Partial Pressures states that in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases. The partial pressure of a gas is the pressure it would exert if it alone occupied the entire volume of the mixture at the same temperature. This exactly matches the statement in the question.

(D) Perfect gas law (or Ideal Gas Law): This law, given by \(PV=nRT\), relates the pressure, volume, temperature, and number of moles of a single ideal gas. While it can be used to calculate partial pressures, the statement itself is Dalton's Law.

(E) Law of equipartition: The equipartition theorem relates the temperature of a system to its average energy. It states that each degree of freedom contributes \(\frac{1}{2}kT\) to the average energy of a particle in the system. It deals with energy, not the summation of pressures in a mixture.

Step 3: Final Answer:
The statement provided in the question is the definition of Dalton's Law of Partial Pressures. This corresponds to option (C).