Question: when nh3 is treated with hcl?
Answer: We also get that after NH3 reacts with HCl, NH3 forms NH4Cl. But the (NH4)+ does not has any lone pair at nitrogen so, the ammonium ion is making the geometry of perfect tetrahedral like the CH4 as a result the bond angle is 109.5 degree. Both NH3 and (NH4)+ are hybridised as sp3.