MCQ
The lanthanide contraction is responsible for the fact that
- A$Zr$ and $Hf$ have same atomic sizes
- B$Zr$ and $Hf$ have same properties
- C$Zr$ and $Hf$ have different atomic sizes
- ✓Both $(a)$ and $(b)$
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| Rate constant | Activation energy | |
| Step $1$ | $k_1$ | $E_{a_1} = 180\,kJ /mol$ |
| Step $2$ | $k_2$ | $E_{a_2} = 80\,kJ /mol$ |
| Step $3$ | $k_3$ | $E_{a_3} = 50\,kJ /mol$ |
overall rate constant, $k = {\left( {\frac{{{k_1}{k_2}}}{{{k_3}}}} \right)^{2/3}}$ overall activation energy of the reaction will be ........ $kJ\,mol$
Statement $I :$ Pure Aniline and other arylamines are usually colourless.
Statement $II :$ Arylamines get coloured on storage due to atmospheric reduction.
In the light of the above statements, choose the most appropriate answer from the options given below: