In the formation of CO it is found that 2.445g of carbon combine with 3.257g of oxygen.?

Question

What is the atomic mass of oxygen if the atomic mass of carbon is 12.01 amu?

Answer 1

15.99859
Carbon combines with Oxygen in a ratio of 1 to 1 when forming Carbon Monoxide. If you find how many moles of Carbon you have, then you can assume you have the same number of moles of Oxygen. Setup the ratio.

[Grams of carbon] / [ grams of Carbon per mole ( 12.01 amu) ] equals the number of moles of Carbon, and also is the number of moles of Oxygen.

2.445g C / 12.01 amu C = moles Carbon=moles Oxygen

grams Oxygen/ amu O =moles Oxygen

or amu Oxygen = grams Oxygen/moles Oxygen

So amu O = ( 3.257g O) / [ (2.445g C)/12.01 amu C)=15.99859

Rounded to 2 decimal places is 16.00 amu