Question

Which of the following statement(s) is are correct for $PC{l}_5$?

• A. $P$ atoms is $s{p}^{3}d$ - hybridized and has trigonal bipyramidal geometry
• B. It acts as a lewis acid
• C. On hydrolysis it forms phosphoric acid
• D. Axial $Cl$ atoms are closer to equatorial $Cl$ atoms

Answer 1

Answer: (A), (B), (C)

The correct options are
A $P$ atoms is $s{p}^{3}d$ - hybridized and has trigonal bipyramidal geometry
B It acts as a lewis acid
C On hydrolysis it forms phosphoric acid

A. P atom is sp³d hybridized and has trigonal bipyramidal geometry because it has 5 sigma bonds and no lone pair. (5+0=5) =>sp³d hybridized)

B. It acts as a Lewis acid because P atom is having vacant d orbital which can accept the electrons (lewis acid).

C. On hydrolysis, it forms phosphoric acid (H₃PO₄). The reaction is: PCl₅ +4H₂O → H₃PO₄ + 5HCl.

D. PCl₅ is a trigonal bipyramidal in which three chlorine atoms are at the corners of the triangle while two chlorine atoms are axial. The bond length of axial bond is greater than the length of the equatorial bond to minimise the bond pair-bond pair repulsion between axial and equatorial bonds.

Hence, options A, B and C are correct.