Final answer:
To find the mass of 9.85 x 10^24 molecules of methanol, convert the number of molecules to moles using Avogadro's number, and then convert moles to grams using the molar mass of methanol. The mass is found to be 523.52 grams.
Step-by-step explanation:
To calculate the mass in grams of 9.85 x 1024 molecules of methanol (CH3OH), we need to use Avogadro's number, which tells us that 1 mole of a substance contains exactly 6.02 x 1023 molecules. The molar mass of methanol is given as 32.0 g/mol. We can use these numbers to set up a conversion from molecules to moles and then to grams.
First, we convert molecules to moles:
9.85 x 1024 molecules CH3OH × (1 mol CH3OH / 6.02 x 1023 molecules) = 16.36 moles CH3OH
Next, we convert moles to grams:
16.36 moles CH3OH × (32.0 g CH3OH / 1 mol CH3OH) = 523.52 grams of CH3OH