Which of the following compounds will form significant amounts of meta product during mono-nitration reaction? Hi, I tried to answer this question based wholly on the concepts of inductive effects. But haven't gotten anywhere with it. 
I would appreciate any help regarding these questions:


What condition makes a compound to give meta product(instead of ortho or para)?
I know there is some flaw with my approach, so what is the correct way to do it?
Can this condition be applied to other compounds as well, or is it just for aromatic compounds?
The answer to the question is (1) Aniline. 

This occurs because under standard strongly acidic nitrating conditions (typically cH2SO4/HNO3) the aniline NH2 is protonated removing the ability of nitrogen lone pair to donate any electrons. Consequently the electron-withdrawing polar effect makes it m-directing. Some p-nitroaniline is formed because there is a small amount of the aniline freebase in equilibrium with the anilinium, but that is much more reactive than the anilinium.

Further reading here

Also discussed in this question  Why does nitration of aromatic amines give meta directed nitro compounds?