1) Temperature because a faster temp means a faster rate of reaction
2) Concentration (water potential level) in osmosis molecules have to move from an area on high water potential to an area of low water potential.also the area of low water potential will contain more sugar molecules than water molecules and the area with a high water potential will contain less sugar molecules than water molecules, meaning that the sugar molecules will moves from the area of low water potential to the area of high water potential. so it's sort of like the two sides are swapping molecules until they're equal. this increase the rate of osmosis if the high water potential side and the low water potential side have a very different level of water, but it will slow down as they share out the water and sugar molecules.
3) The distance the molecules have to move across. so the more distance between the two sides the slow the rate of osmosis
