N(CH3)3 is pyramidal while(SiH3)3N is trigonal planer why?

N(CH₃)₃ has sp3 hybridization & pyramidal shape at N, but in (SiH₃)₃N again there is 2pπ—3dπ back bonding between lone pair orbital of nitrogen into vacant orbital of silicon. Hence trisilyl amines is sp2, planer & is less basic than trimethyl amine.

Calculate the percentage degree of dissociation of an electrolyte XY2 ( normal molar mass=165) in water if the observed molar mass by measuring elevation in boiling point is 65.5.

Which of the following pair of solution (aq.) contain isotonic solution at same temperature? (Assume 100 % ionisation of electrolytes) (1) 0.1 M NaCI and 0.2 M CaCI2(2) 0.1 M NaCI and 0.3 M AICI3 (3) 0.3 M NaCI and 0.1 M AICI3 (4) 0.3 M NaCI and 0.2 CaCI2