The complex formation Tendency of NH3 is wisher than PH3.

SOLUTION: In NH₃ lane pair is present in one of the sp³ Hybridized orbital. While in PH₃ lone pair is present in pure S orbital and hence lane pair donation capacity of NH₃ is stronger than PH₃

What happens if two deactivating and one activating group is present on a benzene ring?

We know that reactivity of benzene ring towards electrophilic reaction depends upon presence of group on benzene ring. Benzene gives electrophilic substitution reaction due to negative pi cloud formation , if there is EWG (electron withdrawing) group on benzene ring it's negativeness decreases and reactivity also decreases and due to resonance upcoming group goes at meta position only while in the presence of ERG (electron releasing groups) it's negative ness increases and reactivity increase and due to resonance upcoming group goes at ortho and para position .

If both EWG and ERG present on benzene ring then upcoming electrophile goes to ortho and para position  according to ERG group .

What is bromoform reaction?

Haloform reaction includes Chloroform, Bromoform and Iodoform reaction, It is feature reaction of terminal methyl ketones and alpha hydroxy ketones . In which methyl ketones oxidised in the presence of I2 and NaOH ( NaOI) into Sodium salt of carboxylic acid and corresponding haloform ( Chloroform , Bromoform and Iodoform)