So do you taste the air or the nothing?

You taste the nothing in the air.

You can taste the air. You're simply so used to it that it is the default to you so you consider it nothing.

the air has the taste of nothing

You mean smell, not taste. Something must be solid or liquid to have taste.

Indeed , but air can also have taste , if it's fart , though.

That's also a smell...

So are you saying we taste scents?

Not me.

Well doesn't air have liquid?
Even if we are used to the taste, that doesn't mean that we don't taste anything.

Plus how come whenever I smell gas I could taste something?

Yes, you can taste smells as well as smell smells.

No, air doesn't have liquid.

It's possible for small droplets of liquid to float through the air, and some vapors might be able to stimulate taste buds.

I agree with Craig, whenever I'n near an area with spilled gasoline (like some car wrecks) I can smell and taste the gas pretty well.

It's possible but they don't last for long. And definitely not in the air.