C: 8 atoms x atomic mass of carbon (12.01 g/mol) = 96.08 g/mol
H: 10 atoms x atomic mass of hydrogen (1.01 g/mol) = 10.10 g/mol
N: 4 atoms x atomic mass of nitrogen (14.01 g/mol) = 56.04 g/mol
O: 2 atoms x atomic mass of oxygen (16.00 g/mol) = 32.00 g/mol
Adding these values together, we get:
96.08 g/mol + 10.10 g/mol + 56.04 g/mol + 32.00 g/mol = 194.22 g/mol
Therefore, the molecular mass of caffeine is approximately 194.22 g/mol.
To find the mass of 1.75 x 10^20 molecules of caffeine, we can use the following equation:
Mass = (Number of molecules) x (Molecular mass)
Mass = (1.75 x 10^20) x (194.22 g/mol)
Calculating the result:
Mass ≈ 3.40 x 10^22 g
Therefore, the mass of 1.75 x 10^20 molecules of caffeine is approximately 3.40 x 10^22 grams.