If an activity consists of participation by all members, and no one feels physical or mental discomfort, and there is no risk of physical or mental harm, then you're probably safe. Piece of cake
Outside of approved new member education lesson plans, there should be no activities that separate the uninitated from the initated to lessen the suspicion of hazing.
Dividing work isn't hazing. It's called delegation and it's the true mark of leadership to be able to distribute the work.
If you need to do a house cleanup, select names at random that include members from all years. Better yet, at the beginning of each school year, give members the opportunity to join committees that are headed by officers of the chapter. The committees will work toward the fulfillment of chapter goals. And by having members involved in the implementation of chapter goals, each member will feel empowered and involved.