Question
Chemistry Question on Stoichiometry and Stoichiometric Calculations
In the reaction:BCl3+PH3⇌Cl3B·PH3 Lewis base is:
A
(A) BCl3
B
(B) PH3
C
(C) CI3B−PH3
D
(D) None of these
Answer
(B) PH3
Explanation
Solution
Explanation:
Given reaction:BCl3+PH3⇌Cl3B·PH3Atomic number of P = 15Electronic configuration of P=1s22s22p63s23p3Atomic number of B = 5Electronic configuration of B=1s22s22p1Therefore, B is electron deficient.Now, 'P' forms three bonds with hydrogen using its three electrons present in 3p-orbitals and 2 electrons remain with P as a lone pair, which it donates to the boron atom.Therefore, Cl3B−PH3 complex is formed by the donation of a pair of electrons from the outer shell of phosphorus of PH to the boron atom of BCl3. Thus, PH3is acting as a Lewis base and BCl3 is acting as a Lewis acid.Hence, the correct option is (B).