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QJEEM11Ch84ff: JEE Main 2011 Chemistry - Class 11 JEEM11Ch84ff Solution: Outer electronic configuration of Gd (Atomic no : 64) is -
Outer electronic configuration of Gd (Atomic no : 64) is -
Multiple Choice Options
- A 4f85d06s2
- B 4f45d46s2
- C 4f75d16s2
- D 4f35d56s2
Step-by-Step Verified Solution
Electronic configuration of Gd(64) : [Xe]4f75s25p65d16s2
So the outer electronic configuration will be : 4f75d16s2
Shortcut Method : Gd belongs to 4f series which is also called lanthanide series. In this lanthanide series for Cerium (Ce), Gadolinium (Gd) and Lutetium (Lu) outer d orbital has 1 electron and for all other lanthanide series elements outer d orbital has 0 electron. From this you can easily say option (C) is correct.
So the outer electronic configuration will be : 4f75d16s2
Shortcut Method : Gd belongs to 4f series which is also called lanthanide series. In this lanthanide series for Cerium (Ce), Gadolinium (Gd) and Lutetium (Lu) outer d orbital has 1 electron and for all other lanthanide series elements outer d orbital has 0 electron. From this you can easily say option (C) is correct.