What is Chirality?
“The property of non-identity of an object with its mirror image is called chirality.”
Chiral centre of the molecule:
“A structural feature within a molecule that is responsible for its chirality is called the chiral centre of the molecule.”
What is meant by chiral carbon?
“The carbon to which four different atoms or groups are attached is called chiral carbon or asymmetric carbon.”
However, a chiral atom is not a necessary condition for chirality. A molecule may not have a chiral atom but still be chiral.
On other hand, a molecule may have more than one chiral atom but still it may be achiral.