Please I need help with this question!!!
Use this data:
Temperature of oxygen gas = 23.0 °C
Volume of oxygen gas = 265.1 mL
Pressure of oxygen gas = 245.6 mm Hg
Mass of oxygen gas = 0.3238 g
Use this data:
Temperature of oxygen gas = 23.0 °C
Volume of oxygen gas = 265.1 mL
Pressure of oxygen gas = 245.6 mm Hg
Mass of oxygen gas = 0.3238 g
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This is obviously an ideal gas law question so we must first remember PV = nRT (say "Piv equals nert"). What we want to determine is R so we must solve for R. Using algebra we see that R = PV/nT.
The second step is to convert all of our input values into the correct units. We know the units we want based on the units of R(L for volume, atm for pressure, mol for amount, K for temperature). We just have to find a way to convert them. I have used MegaConverter (1) for years but there are loads of these web sites out there for you to find on your own.
23C = 296K
265.1 mL = 0.2651 L
245.6 mm Hg = 0.3232 atm (When using megaconverter, you must remember that 1 torr = 1 mm Hg)
Finding the mols of O2 requires a calculation. Wikipedia shows us that the atomic weight of an oxygen atom is 15.9994 (2). We are looking for a volume of oxygen molecules (O2) so the correct molecular weight is 32.00 (I am selecting 4 sig figs because there are 4 sig figs specified in the mass of oxygen).
0.3238 g O2 * 1 mol/(32.00 g O2) = 0.01012 mol O2
Transferring all these numbers into our ideal gas equation which is solved for R we get 0.02859909...
We can't justify this many significant digits so we look at our input with the least significant digits (Temperature) and round our answer off to 3 sig fig.
R = 0.0286 L * atm/(mol * K)
The second step is to convert all of our input values into the correct units. We know the units we want based on the units of R(L for volume, atm for pressure, mol for amount, K for temperature). We just have to find a way to convert them. I have used MegaConverter (1) for years but there are loads of these web sites out there for you to find on your own.
23C = 296K
265.1 mL = 0.2651 L
245.6 mm Hg = 0.3232 atm (When using megaconverter, you must remember that 1 torr = 1 mm Hg)
Finding the mols of O2 requires a calculation. Wikipedia shows us that the atomic weight of an oxygen atom is 15.9994 (2). We are looking for a volume of oxygen molecules (O2) so the correct molecular weight is 32.00 (I am selecting 4 sig figs because there are 4 sig figs specified in the mass of oxygen).
0.3238 g O2 * 1 mol/(32.00 g O2) = 0.01012 mol O2
Transferring all these numbers into our ideal gas equation which is solved for R we get 0.02859909...
We can't justify this many significant digits so we look at our input with the least significant digits (Temperature) and round our answer off to 3 sig fig.
R = 0.0286 L * atm/(mol * K)
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Use the ideal gas law and solve for R.
PV = nRT
R = PV / nT
P = gas pressure in atm = 245.6 mm Hg x (1 atm / 760 mm Hg) = 0.3232 atm
V = gas volume in L = 265.1 mL x (1 L / 1000 mL) = 0.2651 L
n = moles of gas = 0.3238 g O2 x (1 mole O2 / 32.00 g O2) = 0.01012 moles O2
T = Kelvin temperature = 23.0 C + 273.15 = 296.2 K
R = PV / nT = (0.3232 atm)(0.2651 L) / (0.01012 moles)(296.2 K) = 0.02858 L atm / K mole
That's a pretty lousy value since it should be around 0.0821.
PV = nRT
R = PV / nT
P = gas pressure in atm = 245.6 mm Hg x (1 atm / 760 mm Hg) = 0.3232 atm
V = gas volume in L = 265.1 mL x (1 L / 1000 mL) = 0.2651 L
n = moles of gas = 0.3238 g O2 x (1 mole O2 / 32.00 g O2) = 0.01012 moles O2
T = Kelvin temperature = 23.0 C + 273.15 = 296.2 K
R = PV / nT = (0.3232 atm)(0.2651 L) / (0.01012 moles)(296.2 K) = 0.02858 L atm / K mole
That's a pretty lousy value since it should be around 0.0821.