I wouldn't quite say that...
Let's put it this way. Active Skills are things you can do. Knowledge Skills are things you know.
Having a Knowledge Skill in Chemistry means you know the periodic table. You know the difference between a base and an acid. But you can't make homemade chemicals in your basement. All you have is the acedemic theories.
Another, better example... knowledge Firearms. You can rattle off make, model, ammo counts, velocities, etc for guns. Doesn't mean you can hit the broad side of a barn though. That's the active skill.
Obviously there's some loose correlations between skills that differ depending on the type of skill. For Firearms, you can be an expert marksman but not know anything about guns. You don't know nor care who made your gun, you juts know you can pick it up and deadeye a target at 500 meters.
With Chemistry though... Chances are you'd have to know a bit about Chemistry and chemicals to mix chemicals and actually use the Chemistry Active Skill.
So, you milage varies, and it's going to be up to the GM. But the rule of thumb should be... if it's something you actively DO, then it's an Active Skill. If it's something you simply know, then it's a Knowledge skill.
And I miss 3rd Eds complimentary skills, BTW. Because they let you utilize Knowledge Skills in an attempt to put knowledge into practice. Ahh well.
bull