Molar Mass of CO

Carbon monoxide. One carbon and one oxygen. Not to be confused with Co, the element cobalt.

Molar mass of CO
28.010 g/mol
1 × 12.011 + 1 × 15.999 = 28.010

Calculation, element by element

ElementAtomsAtomic mass (g/mol)SubtotalMass %
Carbon (C)112.01112.01142.88%
Oxygen (O)115.99915.99957.12%
Total28.010100%

= 0.35702 mol = 2.15 × 1023 formula units

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CO molar mass FAQ

What is the molar mass of carbon monoxide (CO)?

28.010 g/mol. It is the sum of the atomic masses of every atom in the formula: 1 × 12.011 + 1 × 15.999 = 28.010 g/mol.

How many grams are in one mole of CO?

28.010 g. Molar mass is the mass of one mole (6.022 × 10²³ formula units), so 1 mol of CO weighs 28.010 g and 0.5 mol weighs 14.005 g.

How many moles are in 10 g of CO?

10 g ÷ 28.010 g/mol = 0.3570 mol.

What is the percent composition of CO?

Carbon 42.88%, Oxygen 57.12%.

Is molecular weight the same as molar mass for CO?

Numerically yes: the molecular (or formula) weight is 28.010 u per formula unit, and the molar mass is 28.010 g/mol.

Molar masses of other common compounds