Question

How can you determine the volume of a gas from the number of moles of a gas (at STP)? Use the pattern you identified in the data table to find the mass of an 89.6 L sample of helium. Helium has a molar mass of 4.0 g/mol.

Answer 1

This problem is asking for a methodology for the calculation of the volume of a substance at STP, as well as the mass of helium in an 89.6-L sample. At the end, the calculation turns out to be 16 g and the explanation is that we use the widely-used equivalent statement known as 1 mol = 22.4 L.

What is an Ideal Gas?

In chemistry, the study of ideal gases can be carried out by using the following formula, relating pressure, temperature, volume and moles:

$PV=nRT$

Which are the STP conditions?

Now, if we talk about STP conditions, we refer to a temperature of 273 K and a pressure of 1 atm, so we can calculate the volume in one mole of any gas:

$V=\frac{nRT}{P}=\frac{1mol*0.08206\frac{atm*L}{mol*K}*273K}{1atm}\\ \\ V=22.4L$

This means one can use the following equivalence statement for any mole-volume calculation at STP:

1 mol = 22.4 L.

Furthermore, the mass of helium contained in an 89.6-L sample, can be calculated with the following setup, based on the aforementioned:

$89.6L*\frac{1mol}{22.4L}*\frac{4.0g}{1mol} \\\\16.0gHe$

Learn more about ideal gases: https://brainly.com/question/8711877