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3 years ago

How many atoms are in a 4.7 g copper coin?

Physics

2 answers:

azamat3 years ago

4 0

3.11 is the answer I think

WINSTONCH [101]3 years ago

3 0

Answer:

x = 4.45 * 10 ^22 Note. Technically, this should be rounded to 4.5 * 10^22. There are only 2 sig digits.

Explanation:

You have to assume that the coin is pure copper, which I doubt. What a coin is actually made of depends on when it was minted. But for the sake of this question, we'll assume coins are pure copper.

Copper has an atomic mass of 63.546 grams / mol

So 4.7 g of copper = 4.7 / 63.545 mol

We have 0.07396 mol of copper

1 mol of anything = 6.02 * 10^23 atoms (in this case).

0.07396 mol = x

Cross Multiply

1 * x = 0.07396 * 6.02 * 10^23

x = 4.45 * 10 ^22 atoms of copper

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4 years ago

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4 years ago

How many atoms are in a 4.7 g copper coin?​

How many atoms are in a 4.7 g copper coin?