What are good examples of questions that make college students think about chemistry concepts?
Intermolecular forces

Are there contradictions about intermolecular forces in the postulates of kinetic theory?

Why do molecules having a higher relative molecular mass have stronger inter-molecular forces?
Kinetics of chemical reactions

Does a first order reaction really get completed only at infinity?
Equilibrium and direction of reactions

What does it mean to shift equilibrium?

At equilibrium are the rates of the forward and backward reactions equal to zero?
Acid/base reactions

Is the behavior of a dilute strong acid the same as the behavior of a weak acid?
Redox reactions (electrochemistry)

Why is it important to use a salt bridge in a voltaic cell? Can a wire be used?