#Molar mass of o2 how to#

When calculating molecular weight of a chemical compound, it tells us how many grams are in one mole of that substance. Using the chemical formula of the compound and the periodic table of elements, we can add up the atomic weights and calculate molecular weight of the substance.įinding molar mass starts with units of grams per mole (g/mol).

For bulk stoichiometric calculations, we are usually determining molar mass, which may also be called standard atomic weight or average atomic mass. This is not the same as molecular mass, which is the mass of a single molecule of well-defined isotopes.

#Molar mass of o2 how to#

This is how to calculate molar mass (average molecular weight), which is based on isotropically weighted averages. The atomic weights used on this site come from NIST, the National Institute of Standards and Technology. This site explains how to find molar mass. The reason is that the molar mass of the substance affects the conversion.

To complete this calculation, you have to know what substance you are trying to convert. These relative weights computed from the chemical equation are sometimes called equation weights.Ī common request on this site is to convert grams to moles. In chemistry, the formula weight is a quantity computed by multiplying the atomic weight (in atomic mass units) of each element in a chemical formula by the number of atoms of that element present in the formula, then adding all of these products together.įormula weights are especially useful in determining the relative weights of reagents and products in a chemical reaction. Moles O2 to grams, or enter other units to convert below: Enter two units to convert From: Thus, the formula mass of calcium hydrogen carbonate is 117.10 amu and the molar mass of calcium hydrogen carbonate is 117.10 grams per mole (g/mol).You can do the reverse unit conversion from However when talking about a mole of an ionic compound we will still use the term molar mass. This is because there are no individual molecules in ionic compounds. For compounds that are not molecular (ionic compounds), it is improper to use the term “molecular mass” and “ formula mass” is generally substituted. The molar mass of the N 2 molecule is therefore 28.02 g/mol. This is referred to as the molecular mass and the molecular mass of any molecule is simply the sum of the atomic masses of all of the elements in that molecule. For nitrogen, the mass of the N 2 molecule is simply (14.01 + 14.01) = 28.02 amu. For a molecule (for example, nitrogen, N 2) the mass of molecule is the sum of the atomic masses of the two nitrogen atoms. The concept of molar mass can also be applied to compounds. Further, if you have 16.00 grams of oxygen atoms, you know from the definition of a mole that your sample contains 6.022 x 10 23 oxygen atoms.

For example, the atomic mass of an oxygen atom is 16.00 amu that means the molar mass of an oxygen atom is 16.00 g/mol. Generalizing this definition, the molar mass of any substance in grams per mole is numerically equal to the mass of that substance expressed in atomic mass units. By definition, the molar mass of carbon-12 is numerically the same, and is therefore exactly 12 grams.

We have defined a mole based on the isotopic atomic mass of carbon-12. The atomic mass of an element is the relative average of all of the naturally occurring isotopes of that element and atomic mass is the number that appears in the periodic table. ) a carbon atom with six proton and six neutrons in its’ nucleus, surrounded by six electrons.