What is the mass in grams of 4.28×10^24 molecules of propane (C₃H₈)?
Using the chemical formula for propane C₃H₈, the mass of 4.28×10^24 molecules is approximately 313.89 grams. To calculate the mass in grams, we need to determine the molar mass of propane and then convert the number of molecules to grams.
Calculating the Molar Mass of Propane
To calculate the molar mass of propane (C₃H₈), we sum up the atomic masses of carbon and hydrogen in the molecule:
- C: 3 atoms x atomic mass of carbon (12.01 g/mol) = 3 x 12.01 g/mol = 36.03 g/mol
- H: 8 atoms x atomic mass of hydrogen (1.008 g/mol) = 8 x 1.008 g/mol = 8.064 g/mol
Total molar mass of propane (C₃H₈) = 36.03 g/mol + 8.064 g/mol = 44.094 g/mol
Converting Molecules to Moles
Using Avogadro's number (6.022 × 10²³ molecules/mol), we convert the number of molecules to moles:
4.28×10^24 molecules of propane x (1 mol / 6.022 × 10²³ molecules) = 7.11 mol
Calculating the Mass in Grams
Finally, we calculate the mass in grams using the molar mass and moles obtained:
Mass = moles x molar mass
Mass = 7.11 mol x 44.094 g/mol ≈ 313.89 grams
Therefore, the mass of 4.28×10^24 molecules of propane is approximately 313.89 grams.