`CIF_3` exists but `FCI_3` does not. Why?

Explain i) Sulphur vapours, exhibits some paramagnetism ii) ClF , exists but F C l_3 does not. iii) N(CH_3)_3 , is pyramidal but N(SiH_3)_3 is planar. iv) Interhalogen compounds are more reactive than the corresponding, elemental hálogens?

Why does R_3P=0 exist but R_3N=0 does not. [R = alkyl group]?

PCl_5 and PH_3 exist but PH_5 does not because

Which of the following statements is/are correct on the basis of hydrogen bond ? (1) KHF2 exists but KHCl2 does not. (2) Boiling point order of hydrogen halides is HF>HI>HBr>HCl (3) CCl3 CH (OH) 2 and o- nitrophenol show intermolecular hydrogen bond (4) All are correct

Write two matrices A and B for which AB exists but BA does't exist

Why does NH3 form hydrogen bond but 'PH3 does not?

Chloroform is generally prepared from ethanol. Iodoform gives a precipitate with AgNO_3 solution while chloroform does not. Why ?

Why is Li_2CO_3 decomposed at a lower temperature where as Na_2CO_3 does not?