The NH3 molecule, which consists of one lone pairs and three bond pair of electron on its valance shell due to lone pair bond pair repulsion makes bond angle of 107.5°resulting distorted tetrahedral geometry.
Hybridization =no. of bond pair +lone pair=3+1=4=sp3 hybridization
There are two direct factors that affect solubility: temperature and pressure. Temperature affects the solubility of both solids and gases, but pressure only affects the solubility of gases.