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katrin [286]
2 years ago
13

How many atoms are in a sample of 68.7 grams copper (Cu)?

Chemistry
2 answers:
qwelly [4]2 years ago
8 0
First find the moles of the substance: Moles = mass / RFM 

moles = 68.7 / 
kondaur [170]2 years ago
7 0
To find the number of atoms in the sample of copper, we need its atomic mass and the use of the Avogadro's number to find the equivalent units in terms of atoms.

68.7 g Cu ( 1 mol / 63.55 g ) ( 6.022 x 10^23 atoms / 1 mol ) = 6.51 x 10^23 atoms Cu
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Explanation:

Attached below you can find the diagram I found for this question elsewhere.

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