Final answer:
To calculate the number of water molecules in 0.500 moles of water, multiply 0.500 moles by Avogadro's number, resulting in 3.011×1023 molecules of H2O.
Step-by-step explanation:
The question asks how many water molecules are in a block of ice containing 0.500 mol of water (H2O). To find the number of water molecules, we can use Avogadro's number, which states that one mole of any substance contains 6.022×1023 particles of that substance. Therefore, to calculate the number of water molecules in 0.500 moles of water, we multiply 0.500 moles by Avogadro's number.
Number of water molecules = 0.500 moles × 6.022×1023 molecules/mole = 3.011×1023 molecules of H2O.