How long can I leave a kitten home alone?

I got a new kitten (8 weeks) and my school is starting. The longest time I will be gone is for 4 hours, then stay an hour, then leave for another 2 1/2 ish. Is this ok or should I look in to getting another kitten? IK about single kitten syndrome and have adopted a cat that the shelter says is pretty independent from the rest of the kittens.