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A toy top has a mass of 32.0 g cu. how many atoms cu are in this spinning top, given that the average atomic mass of copper is 63.55 g/mol cu?

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Answer:

3.03 x 10²³ atoms Cu

Step-by-step explanation:

To find the amount of copper atoms, you need to (1) convert grams to moles (via average atomic mass) and then (2) convert moles to atoms (via Avogadro's number). The final answer should have 3 sig figs because the given value with the lowest amount of sig figs (32.0) also has 3 sig figs.

Avogadro's Number:

6.022 x 10²³ atoms = 1 mole

32.0 g Cu 1 mole 6.022 x 10²³ atoms
---------------- x ---------------- x -------------------------------- = 3.03 x 10²³ atoms Cu
63.55 g 1 mole

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