Question

What volume will 20 g of argon occupy at STP (Standard Temperature and Pressure)?

a) 22.4 L
b) 11.2 L
c) 44.8 L
d) 33.6 L

Answer 1

The volume of 20 g of argon at STP is calculated to be 11.2 L, based on the molar volume of a gas at STP, which is 22.4 L/mol.

Step-by-step explanation:

The question asks about the volume occupied by argon gas at Standard Temperature and Pressure (STP). To find this volume, we can use the molar volume of a gas at STP, which is 22.4 liters per mole according to the Ideal Gas Law. Argon has a molar mass of approximately 40 g/mol, so to determine the number of moles in 20 g of argon, we divide the mass of argon by its molar mass:

• Number of moles = mass / molar mass = 20 g / 40 g/mol = 0.5 mol

Now, we can calculate the volume that 0.5 mol of argon would occupy at STP by multiplying the number of moles by the molar volume:

• Volume = number of moles × molar volume = 0.5 mol × 22.4 L/mol

This results in 0.5 × 22.4 = 11.2 L, which is option b), and represents the volume that 20 g of argon will occupy at STP.