The catalytic activity of transition elements is related to their
variable oxidation states
surface area
complex formation ability
All of the above
Identify incorrect statement
The element exhibiting most stable $ + \,2$ oxidation state among the following is
$(a)$ Answer the following questions :
$(i)$ Which element of the first transition series has highest second ionisation enthalpy ?
$(ii)$ Which element of the first transition series has highest third ionisation enthalpy ?
$(iii)$ Which element of the first transition series has lowest enthalpy of atomisation ?
$(b)$ Identify the metal and justify your answer.
$(i)$ Carbonyl $M(CO)_5$ $(ii)$ $MO_3F$
Given below are two statements, one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A:$ The spin only magnetic moment value for $\left[ Fe ( CN )_6\right]^{3-}$ is $1.74 BM$, whereas for $\left[ Fe \left( H _2 O \right)_6\right]^{3+}$ is $5.92\,BM$.
Reason $R :$ In both complexes, $Fe$ is present in +3 oxidation state.
In the light of the above statements, choose the correct answer from the options given below:
The transition metal ions responsible for colour in ruby and emerald are, respectively