9701 MCQ Solution 54

Question 54: [Physical > Bonding]

Aluminium chloride catalyses certain reactions by forming carbocations (carbonium ions) with choloralkanes as shown.

Which property makes this reaction possible?

A AlCl3 is a covalent molecule.

B AlCl3 exists as the dimer Al2Cl6 in the vapour.

C The aluminum atom in AlCl3 has an incomplete octet of electrons.

D The chlorine atom in RCl has a vacant p orbital.

Reference: Past Exam Paper -June 2003 Paper 1 Q14

Solution 54:

Answer: C.

The aluminium atom has an incomplete octet of electrons therefore it will form co-ordinate bonds ti have a complete octet of electrons therefore this reaction is possible.