Question

A 385 cm3 sample of carbon dioxide at 100 kpa and 25 °c was mixed with 2.89 × 10−2 mol of argon. the gas constant, r = 8.31 j k−1 mol−1 what is the mole fraction of carbon dioxide in the mixture?

Answer 1

The mole fraction of carbon dioxide in the gas mixture is determined by first calculating the moles of carbon dioxide using the ideal gas law, then adding it to the known moles of argon, followed by dividing the moles of carbon dioxide by the total moles in the mixture.

Step-by-step explanation:

To determine the mole fraction of carbon dioxide (CO2) in the mixture with argon (Ar), we need to first find the number of moles of CO2. We use the ideal gas law for this purpose, which is PV = nRT. Given that we have a volume (V) of 385 cm3 (or 0.385 L), a pressure (P) of 100 kPa, a temperature (T) of 25 °C (which is 298.15 K after converting to Kelvin), and the universal gas constant (R) of 8.31 J K-1 mol-1, we can solve for n (the number of moles of CO2).

First, let's convert the pressure into Pa by multiplying by 1000, since 1 kPa = 1000 Pa.

We rearrange the ideal gas law to solve for n (the number of moles of CO2): n = PV / RT.

After calculating n for CO2, we can find the mole fraction by adding the number of moles of CO2 to the given moles of Ar (2.89 × 10-2 mol), and then dividing the moles of CO2 by the total moles. This will give us the mole fraction of CO2 in the gas mixture.