The two main components in air are nitrogen and oxygen gas. Air is 79% N2 and 21% O2 by volume. Considering
only N2 and O2 in air, calculate the density of air at 1.0 atm, 25 C
a) 0.590 g/L
b) 1.18 g/L
c) 2.46 g/L
d) 14.1 g/L
e) None of the above.
Please help I do not understand!
only N2 and O2 in air, calculate the density of air at 1.0 atm, 25 C
a) 0.590 g/L
b) 1.18 g/L
c) 2.46 g/L
d) 14.1 g/L
e) None of the above.
Please help I do not understand!
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At 1 atm and 25 ºC 1 mole of gas will occupy 24.465 L. (see reference below). 1 L will have 1/24.465 = 0.04087 moles; 79% is N2, or 0.79*0.04087 = 0.03229 mol N2 and 0.21*0.0446 = 0.008583 mol O2.
The molar mass of O2 is 32 g/mol and for N2 = 28 g/mol; the total mass in 1 L is then
28*0.03229 + 32*0.008583 = 1.18 g so the density is 1.18 g/L
The molar mass of O2 is 32 g/mol and for N2 = 28 g/mol; the total mass in 1 L is then
28*0.03229 + 32*0.008583 = 1.18 g so the density is 1.18 g/L