Is 1 tsp and 1 food -pellet?- enough for a dying cat?

My cat is sick, as you can see if you look at my previous question, and I managed to put around 1 tsp of water in his mouth and one piece of dried food, and I plan on doing that again later tonight. Is that ok? Or not enough? If I could I'd give him more water, but the food is not really working out, He is also going to the vet tmr at 9:40 a.m. (its around 7:00 p.m. right now) do you think at the most 5 more pieces of food and at the most probably 2 tsp, will that last him until the appt? I've been giving him 1/4 tsp (from those measuring cups) at a time because I don't have one of those dropper things. So my point is: Will 5 pieces of food (maybe less if he's being stubborn) and 2 tsp (again maybe less) be ok? How long does it take for cats to dehydrate?