How to do 124th question?

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1 Answer
Mar 22, 2018

Would it not be #"number 2"#....?

Explanation:

Mulitple choice question require the best answer from the given alternatives...and sometimes #"best answer"-="least wrong"#..

Now here we look at the four options...#(1)# and #(3)# are clearly whack...we are left with #(2)# and #(4)# for consideration....

Now for #4#, the number of #"d-electrons"# CLEARLY may not the be same...why not? Because we could have filled #3d#, #4d#, #5d# orbitals.... On the other hand the number of valence electrons...i.e. the valence electronic structure should be the same or similar....

Would you post the answer you are given?