In: Chemistry
What is the Lewis acid in the following reaction?
Fe3+(aq) + 6 CN-(aq) ⇄ Fe(CN)63-(aq)
| 
 Fe3+(aq)  | 
 HCN(aq)  | 
 CN-(aq)  | 
 Fe(CN)63-(aq)  | 
 Fe(OH3(aq)  | 
According to the definition of Lewis acid, an ion / metal centre / compound which can accept the election pair from an electron donating substance, that is known as Lewis acid. Simply Lewis acid is electron acceptor.
Now in the above example, Fe 3+ acts as Lewis acid, because it is electron deficient metal centre. H + is also a Lewis acid, and it also comes into the class of Bronsted acid.