MCQ
To which block is an element, having electronic configuration $\ce{1 s^2 2 s^2 2 p^6 3 s^2 3 p^6 3 d^{10} 4 s^1,}$ related in the periodic table?
- A$s−$ block
- B$p−$ block
- ✓$d−$ block
- D$f−$ block
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$aCr _2 O _7^{2-}+ bSO _3^{2-}( aq )+ cH ^{+}( aq ) \rightarrow 2 aCr ^{3+}( aq )+ bSO _4^{2-}( aq )+\frac{ c }{2} H _2 O ( l )$
the coefficients a, b and $c$ are found to be, respectively-