Mini-Mods: General Chemistry - Moles

Created Feb. 7, 2024 by Paul Cooper

Mass to Number Calculations

Now that you've seen how to relate the number of atom or molecules to moles through Avogadro's number, in addition to the relationship between mass and moles through the molar mass, it is clear that moles is a common unit in both processes. Moles is a common unit in many chemical calculations and can be used as a "go-between" to convert between all different kinds of quantities. Here we will just look at converting between what we've already seen - mass to moles to number.

How many molecules of glucose are there in 10.0 g?

Starting with mass we need to convert to moles first using the molar mass of glucose (180.2 g/mol). A second conversion is then required to convert to number using Avogadro's number.

10.0 \mathrm{\:g\: C_{6}H_{12}O_{6}}\: \times \frac{1\: \mathrm{mol}}{180.2\: \mathrm{g}} \times \frac{6.022\times 10^{^{23}}\: \mathrm{molec}}{1\: \mathrm{mol}}=3.34\times 10^{^{22}}\:\mathrm{molec}


Mass to Number


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