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CHEMISTRY
Mole Calculations
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Mole Calculations

What is a mole?

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Mole: the amount of a substance that contains 6.02 x 10^23 representative particles of that substance
 
So how do you find grams from moles and moles from grams?
 
You use DIMENSIONAL ANALYSIS! If you don't know how to do that, you might as well quit chemistry. But, assuming you know dimensional analysis, this is how you do it...
 
Calculate the molecules in 2.3 grams of NH4 SO2
 
 

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Find how many grams are in 3.3x10^23 molecules of N2I6

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How do you find how many moles are in a quantity?
 
How many moles are in 25g of NaCl

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But what about STP??
 
STP stands for "standard temperature and pressure".
STP is 22.4 liters.
 
Find how many liters is 92.86 grams of oxygen gas at STP

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