Question

7. What volume does a sample of 1.5 x 1023 atoms of helium at STP represent?

a) 5.6 liters b) 11.2 liters c) 17.8 liters d) 22.4 liters

Answer 1

a) 5.6 L

Step-by-step explanation:

Step 1: Given data

Atoms of helium: 1.5 × 10²³ atoms

Conditions: Standard temperature (273.15 K) and pressure (1 atm)

Step 2: Calculate the moles corresponding to 1.5 × 10²³ atoms

To convert atoms to moles, we will use Avogadro's number: there are 6.02 × 10²³ atoms of helium in 1 mole of atoms of helium.

1.5 × 10²³ atoms × 1 mol/6.02 × 10²³ atoms = 0.25 mol

Step 3: Calculate the volume of 0.25 moles of He at STP

At STP, 1 mole of helium occupies 22.4 L.

0.25 mol × 22.4 L/1 mol = 5.6 L