Question

A gas mixture containing CH₄ and ¹/₂ has a total pressure of 730 torr at 35 °C. If the partial pressure of ¹/₂ is 330 torr, what is the mole tion of CH₄?

a) 0.547
b) 0.453
c) 0.653
d) 0.347

Answer 1

To find the moles of CH₄ in a gas mixture, we can use Dalton's Law of Partial Pressures and the ideal gas law. By subtracting the partial pressure of ¹/₂ from the total pressure, we can determine the partial pressure of CH₄.

Then, using the ideal gas law, we can calculate the moles of CH₄.

Step-by-step explanation:

To solve this problem, we can use Dalton's Law of Partial Pressures.

According to Dalton's Law, the total pressure of a gas mixture is equal to the sum of the partial pressures of each component gas. In this case, we are given the total pressure of the gas mixture (730 torr) and the partial pressure of ¹/₂ (330 torr).

To find the partial pressure of CH₄, we can subtract the partial pressure of ¹/₂ from the total pressure: 730 torr - 330 torr = 400 torr. Now, we can use the ideal gas law to find the moles of CH₄:

PV = nRT,
where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature.

Rearranging the equation, we get:

n = PV / RT,
where P is the partial pressure of CH₄, V is the volume, R is the ideal gas constant, and T is the temperature.

Plugging in the values, we get:

n = (400 torr) * (20 L) / (0.0821 L atm/mol K * 308 K) ≈ 1.663 mol.