A CHEMIST NEEDS 0.00655 MOL OF BILIRUBIN (C33H36N4O6) FOR AN EXPERIMENT. HOW MANY GRAMS OF BILIRUBIN WILL THAT BE?

You were given a molecule of Bilirubin, a complex organic molecule, of formula: [tex]C_{33}H_{36}N_4O_6[/tex]. Thus, you have here 1 mol of Bilirubin, and below you have molar mass of each element in the molecule:

[tex]C = 12.011[/tex] grams per mol
[tex]H = 1.008[/tex] grams per mol
[tex]N = 28.02[/tex] grams per mol
[tex]O = 16[/tex] grams per mol

Now, you need to multiply each value by the numbers in the formula, let's do this:

[tex]C_{33} = 12.011 \times 33= 396.363[/tex]
[tex]H_{36} = 1.008 \times 36 = 36.288[/tex]
[tex]N_4 = 28.02 \times 4 = 112.08[/tex]
[tex]O_6 = 16 \times 6 = 96[/tex]

And then, adding all those values together we have: [tex]640.731[/tex] grams in one molecule of Bilirubin.

Step 2 - Criss-cross with data

Now that we have all data we need, we can find out how many grams are in 0.00655 mols of bilirubin for the experiment, for that you criss cross the information forming a mathematical equational.

[tex]1 \text{ mol of Bilirun} \rightarrow 640.731 \text{ grams}\\0.00655 \text{ mol of Bilirun} \rightarrow x \text{ grams}[/tex]

[tex]0.00655 \times 640.731 = x\\x = 4.19 \text{ grams}[/tex]