Help please. I dont understand

[name_ask17]

1. The problem statement, all variables and given/known data

The estimated average concentration of carbon monoxide in air in the United States in 1991 was 6.0 ppm. Calculate the number of CO molecules in 1.0 L of this air at a pressure of 601 torr and a temperature of 20.°C.



2. Relevant equations

pv=nrt

3. The attempt at a solutionI tried this and using pv=nrt
pressure was converted to torr
volume was 1
r was taken as 8.31
temp was converted into K
and then...
n was solved for, and muktiplied by avagadro's number
Am i missing something? am i supposed to include the ppm?
i am so confused.
please help.

[Borek]

ppm (http://www.chembuddy.com/?left=concentration&right=ppm-ppb-ppt) is a concentration, so yes, it should be included in your calculations - otherwise you calculated just the number of molecules of all gases in the given volume.

Unfortunately, question is ambiguous - it doesn't state whether ppm is weight/weight or volume/volume.