Question

Question #2c148

Answer 1

That volume of nitrogen gas would contain 20.6 moles at STP.

By definition, STP conditions imply a pressure of 100 kPa and a temperature of 273.15 K. Under these conditions, 1 mole of any ideal gas occupies exactly 22.7 L - this is known as the molar volume of a gas at STP.

Since you know the volume 1 mole would occupy under these condtions, you can determine how many moles you have in 467 L by

`467cancel("L") * "1 mole"/(22.7cancel("L")) = "20.57 moles"` `N_2`

Rounded to three sig figs, the answer will be

`n_(N_2) = color(green)("20.6 moles")`

SIDE NOTE Many problems still use the old definition of STP, which implies a pressure a 1 atm and a temperature of 273.15 K. Under these condtitions, the molar volume of a gas is equal to 22.4 L.

If your teacher wants you to use the old value for the molar volume of gas at STP, simply redo the calculation using 22.4 L, instead of 22.7 L.