How much does a mole weigh?
You can have a dozen eggs, and that would weigh about 12oz. A dozen donuts would weigh about 24 ounces, and a dozen cornflakes would weigh about 6 grams.
Likewise, a mol of atoms has a different weight, depending on what atom you're talking about.
If I wanted to know how much a dozen eggs weighed, I could take the average weight for one egg and multiply by 12:
1 oz * 12 = 12 oz = 1 dozen eggs
On the other hand, a dozen cans of soda would have a different weight:
12 oz * 12 = 144 oz = 1 dozen cans of soda
That was easy. We could do the same thing with atoms -- for example, a mol of helium:
.0000000000000000000000664 g * 602,200,000,000,000,000,000,000 = ???
Two problems here:
How did I know how much a helium atom weighs?
What a nasty computation!!! Miss a few zero's and you're completely screwed. There must be an easier way...
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