Question

Which of the following statements is true?
(i) All stereocentres are chiral centres.
(ii) All chiral centres are stereocentres.
(iii)
(iv) The term chiral centre can be applied to other atoms too.

• A. $(ii), (iii) $ and $(iv)$
• B. $(i), (ii)$ and $(iv)$
• C. $(ii)$ and $(iv)$
• D. $(ii)$ and $(iii)$

Answer 1

Answer: (B)

A stereocentre may be chiral or achiral (e.g., maleic acid has two stereocentres, none of them is chiral). However, all chiral centres are stereocentres - an atom having tetrahedrally bonded to four different atoms or groups is known as chiral centre. The $C ^{+}$ of a carbocation uses $s p^{2}$ hybrid orbitals, i.e., it has a flat geometry and hence it has a plane of symmetry. A chiral centre may be $C , N , S , P , Si$, etc.