fraction by volume = mols fraction.
2.6E-6 = fraction by volume.
2.6E-6 x 106 = ppm = 2.6 but wikipedia shows it as 18 ppm.
The mole fraction of neon in the air is about .0000026. If the average molar mass of air is 28.96 g/mol, what is the concentration of neon in air in ppm?
How do you set this up?
2 answers
MOLAR MASS OF NEON=20,18 AND MOLAR MASS OF AIR=28.96 GIVEN THAT MOLE FRACTION OF NEON:AIR=2.6^-5
PPM MEANS PARTS PER MILLION
I THE DERIVED A FORMULA
C=?
LET
MOLAR MASS OF AIR=A
MOLAR MASS OF NEON=N
MOLE FRACTION OF THE TWO=D
MILLION=1000000
THEN
HERE WE GO.
C=((N/A)(D))(1000000)
1. N/A=20.18/28.96=0.6968232044
2.(N/A)(D)=
(6.968*10^-1)(2.6*10^-5)=1.811740331*10^-5
3.(1.811740331*10^-5)(1000000)=18.11740331 ppm to two significant figures it is equal to 18 ppm
PPM MEANS PARTS PER MILLION
I THE DERIVED A FORMULA
C=?
LET
MOLAR MASS OF AIR=A
MOLAR MASS OF NEON=N
MOLE FRACTION OF THE TWO=D
MILLION=1000000
THEN
HERE WE GO.
C=((N/A)(D))(1000000)
1. N/A=20.18/28.96=0.6968232044
2.(N/A)(D)=
(6.968*10^-1)(2.6*10^-5)=1.811740331*10^-5
3.(1.811740331*10^-5)(1000000)=18.11740331 ppm to two significant figures it is equal to 18 ppm
1 answer