- A$_{21}Sc = [Ar]\, 3d^1\, 4s^2$
- B$_{89}Ac = [Rn]\, 5f^0 \,6d^1 \,7s^2$
- C$_{29}Cu = [Ar] \,3d^{10} \,4s^1$
- ✓All are correct
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Statement- $I$: Along the period, the chemical reactivity of the element gradually increases from group $1$ to group $18$.
Statement - $II$: The nature of oxides formed by group $1$ element is basic while that of group $17$ elements is acidic.In the the light above statements, choose the most appropriate from the questions given below:
Statement $(I)$ : The $4 \mathrm{f}$ and $5 \mathrm{f}$ - series of elements are placed separately in the Periodic table to preserve the principle of classification.
Statement $(II)$ :$S$-block elements can be found in pure form in nature. In the light of the above statements, choose the most appropriate answer from the options given below :