organic, inorganic, in organic

Organic or organic, scientifically, describes something alive, or that was once alive; an animal, plant, or vegetable--
That's right, the stick is organic, because it came from a tree.
We will be studying organic chemistry next semester.

Organic, more commonly, describes food or other products grown or produced without chemicals--
She tries to buy only organic foods, with no additives or preservatives.
There is a new organic market opening next week.

Inorganic or inorganic ( one word ), scientifically, describes something that is not alive, and that never was alive, such as a rock--
This rock is inorganic--it has never been alive.
He failed inorganic chemistry, and has to take it again.

In organic or in organic ( two words ) means within a place, space, or condition ( in ) of something grown without chemicals ( organic )--
He invested all of his money in organic farming.
In organic ( two words ) may also mean within a place, space, or condition ( in ) of something alive; something of plant or animal origin ( organic )--
He got a good grade in organic chemistry; he hopes to go into research when he graduates.

Now that you know that, you can say--
"On our exam in organic chemistry, the teacher asked if a rock with a fossil is organic or inorganic. I argued both sides."