1. Converting between Moles, Mass and Number of Particles Number of Particles to Mass
Chemistry 11
Ms. McGrath

2. Number of Particles to Mass
What is the mass of 5.67 x 1024
molecules of cobalt (II) chloride, CoCl2?
Convert the number of molecules into moles by dividing by the Avogadro’s constant.
Convert the number of moles into grams by multiplying it by the molar mass of cobalt (II) chloride.

3. Number of Particles to Mass
Convert number of particles into moles
n = N NA
n = 5.67 x 1024 molecules
6.02 x 1023 molecules / mol
n = 9.42 mol

4. Number of Particles to Mass
2. Convert the moles to mass
MCoCl2 = g / mol + 2(35.45 g / mol)
= g / mol
m = n x M
= 9.42 mol x g / mol
= 1.22 x 103 g

5. Number of Particles to Mass
Page 63 #28, 29, 30, 31, 32, 33
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