Phenyl group is known to extract negative inductive effect, but each phenyl ring in biphenyl is more reactive than benzene towards Electrophilic substation. Why?

It is because, in biphenyl, one of the phenyl groups acts as donor and the other as electron acceptor. This increases electron density on benzene ring and facilitates Electrophilic attack at ortho and para position.

Are all the five bonds of PCl5 equivalent? Justify your answer.

PCl₅ has Sp³ hybridisation and trigonal bipiramidal geometry. PCl₅ has three equivalent equatorial and two equivalent axial P – Cl bonds. However, due to greater bond pair – bond pair repulsions, the axial P – Cl bonds are longer and hence different from the three equatorial bonds

Halides of Nitrogen Family:

Silianol (SiH3OH) is more acidic than methanol (CH3OH) why?

We know that acidic strength of an acid also depend upon stability of its conjugate base. So silianol is more acidic than methanol (H₃C-OH) because conjugate base silianol (H₃Si-OH) stablised by dispersal of negative charge in H₃Si-O- ion by 2pπ—3dπ back bonding

Hence methanol is less acidic than silianol.

For more detail on Back bonding click here

Related Questions: 

(1) Although anhydrous aluminium chloride is covalent but its aqueous solution is ionic in nature. Why?

(2) Why Ga has small size than Al exceptionally

(3) Why aqueous solution of borax reacts with two moles of acids ?

(4) What is structure of solid Ortho Boric acid ?

(5) What is the structure of trimetaboric acid and trimetaborate ion?  

(6) Why Borazine is more reactive than benzene towards Electrophic Aromatic substitution reactions ?

(7) Why Borazine (B3N3H6) is also known as inorganic benzene ?.

(8) Why B-F bond length in BF3 is shorter (130 pm) than B-F bond Iength in BF4- (143 pm)?. Explain.

(9) Why B-F do not exist as dimer?. Explain.

(10) Although anhydrous aluminium chloride is covalent but its aqueous solution is ionic in nature. Why?

(11) Why Boric acid become strong acid in the presence of cis 1,2-diol or 1,3-diol ?