Ok, I'm doing some chem homework and trying to figure out this question. Using the ideal gas law (pV=nRT): What volume would be occupied by 100 g of oxygen gas at a pressure of 1.5 atm and a temperature of 25 degrees C? Thanks!
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Chemistry Question...Help!
- Thread starter ipodtouchy333
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you have to convert 100 g of oxygen number into number of moles of oxygen. hint: use the periodic table of elements to get the weight of one mole of oxygen.
n is the number of moles of the product you're working with, in this case oxygen.
If you take a look at the periodic table you'll note that Oxygen's molar mass is 15.9994 g/mol meaning that 15.9994 grams of oxygen is equivalent to one mol of oxygen. A mole incase you aren't familiar with the term is an atom or molecule count, it represents 6.022x10^23 particles (or any item really).
So what you do is take your 100 g of oxygen and divide it by the 15.9994 grams that constitute each mol of Oxygen and that gives you your # of moles. In this case it's (100g)/(15.9994g/mol)=6.25 mol
You then take that mol amount and use it as your n figure in the PV=nRT equation. Isolating for the variable you're interested in, which for this question is Volume.
So: V=(nRT/P)
plug in your values and you have
V=((6.25mol)(0.082 057 46(Lxatm/molxK)(298K))/(1.5atm)
All units save the litres cancel out and you're left with a volume of 229.248 Litres.
I've done your homework for you, but I've outlined just how it's done so make sure you learn it now!
SLC
If you take a look at the periodic table you'll note that Oxygen's molar mass is 15.9994 g/mol meaning that 15.9994 grams of oxygen is equivalent to one mol of oxygen. A mole incase you aren't familiar with the term is an atom or molecule count, it represents 6.022x10^23 particles (or any item really).
So what you do is take your 100 g of oxygen and divide it by the 15.9994 grams that constitute each mol of Oxygen and that gives you your # of moles. In this case it's (100g)/(15.9994g/mol)=6.25 mol
You then take that mol amount and use it as your n figure in the PV=nRT equation. Isolating for the variable you're interested in, which for this question is Volume.
So: V=(nRT/P)
plug in your values and you have
V=((6.25mol)(0.082 057 46(Lxatm/molxK)(298K))/(1.5atm)
All units save the litres cancel out and you're left with a volume of 229.248 Litres.
I've done your homework for you, but I've outlined just how it's done so make sure you learn it now!
SLC