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Name: mark s scheiber
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1999 


Question:
Does air have mass?



Replies:
Yes, it does. It just isn't very dense, so there isn't as much matter in a cup of air as there is in a cup of water. However, it does have mass, and you can calculate it. Let's say I have 1 liter of air at 1 atm of pressure and at 25 degrees Celsius (298K). I can use the equation PV = nRT (the gas law) to calculate n, the number of moles of air, given that R is a constant equal to 0.0821. Now, if you assume that about 70% of those moles are nitrogen gas (weighing 28 grams per mole) and 30% are oxygen (weighing 32 grams per mole) you can estimate how many grams of air you would have.

Try it out!

topper



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