Which of the following has a yellow colour?

$A$ blue colouration is not obtained when:

In which of the following complexes is the pairing of $(n-1)d$ electrons $NOT$ present in the presence of strong field ligands $(SFL)$?

The ammonia prepared by treating ammonium sulphate with calcium hydroxide is completely used by $NiCl_2 \cdot 6H_2O$ to form a stable coordination compound. Assume that both the reactions are $100 \%$ complete. If $1584 \ g$ of ammonium sulphate and $952 \ g$ of $NiCl_2 \cdot 6H_2O$ are used in the preparation,the combined weight (in grams) of gypsum and the nickel-ammonia coordination compound thus produced is $\qquad$ (Atomic weights in $g \ mol^{-1}: H=1, N=14, O=16, S=32, Cl=35.5, Ca=40, Ni=59$)

Which of the following compounds is not colored yellow?

Consider the following complexes:
$(a) \ Na_2[Fe(CN)_5NO]$
$(b) \ [Fe(H_2O)_5NO]SO_4$
$(c) \ K_4[Fe(CN)_6]$
Which of the following statements is wrong?