Questions that needed answers

Am copying a recipe down because am thinking about doing it. A question just pop into my mind. Can most batter wait? What do I mean by that?

You see, mine is a small oven that can only fit in a tray of twelve mini cupcakes nicely. What happen if the recipe I am following can make more than 12 ? Should I half the recipe, or should I get two trays? If I bake one first, can the batter wait? Will the waiting time allows chemical reaction to take place within the batter? I am sure some batter can survive the waiting time, some cannot. But I wouldn't know what can and what cannot.

So how?