How many atoms are in a sample of 68.7 g of copper

1 answer:

7 0

First, you must find the number of moles of copper that your sample has. This is calculated by #of moles= your sample mass (in grams)/ atomic mass (in grams)
#of moles=68.7g/63.546g
#of moles= 1.08 moles present

Then to find the number of atoms present, we must multiply the number of moles present in the sample with Avogadro's number, which is 6.022x10^23 (this number is the number of atoms present in each mole)
# of atoms present in copper sample=1.08(6.022x10^23)
#of atoms present in copper sample= 6.50x10^23

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