You can’t see through it (very far)!
(homogeneous mixtures) that are made up of substances in the fluid phase – composed of liquids or gases, or any combination of the two – must be transparent. So air, which is a mixture of gases – nitrogen, oxygen and trace amounts of other – IS considered homogeneous.
However, I imagine that there are a good deal of pollutants in the air in New York, and for that reason it probably appears a little hazy – that is, there are fine particles suspended in the air. You could probably detect them by passing the air through a filter (check your furnace filter if you have access to it, and you’ll see what I mean.) So, because of this fine particulate matter in the air, it is classified as heterogeneous, and more accurately as an aerosol or colloidal, though it may be classified as a suspension (depending on the size of the particles.)
