chemistry help pls

Question

What is the difference in volume between A) 4.705 g of carbon monoxide at 349 K and B) the same mass of carbon dioxide at 581 K if they are both at 90.1 kPa?

Answer 1

Hello,Molly,

Use the Ideal gas law: PV = nRT

Since we are given pressure in kPa, use the gas constant (R) with units of kPa.

I used R = 8.314 kPa*L*K^-1mole^-1

Calculate the moles of each gas by dividing the grams by the molar mass of each gas:

CO = 0.168 moles

CO₂ = 0.1069 moles

One might suspect, since both gases are at the same pressure, that the additional moles of CO would cause it to have a higher volume. But the CO2 is at a higher temperature, so that would cause expansion of the gas. The CO gas is at 349K, while the CO2 is at 581K

Make a table and plug the numbers in the rearranged equation. Make sure the units cancel to leave only volume (in Liters).

V = nRT/P

V (CO) = 5.41L

V (CO₂) = 5.73L

Bob