How many of the following order of size is/are not incorrect?≃ (i) S c B e + 2 A l + 3 (iii) A l G a I n (iv) O 2 −

Question

How many of the following order of size is/are not incorrect?>≃

(i) $S c < Y < L a$

(ii) $L i^{+} > M g^{+ 2} > B e^{+ 2} > A l^{+ 3}$

(iii) $A l > G a > I n$

(iv) $O^{2 -} < C l^{-}$

(v) $B r^{-} < H^{-} > I^{-}$

(vi) $C u < Z n$

(vii) $N i < P d ≃ Pt$

TestHub · Accepted Answer

There are 5 correct (not incorrect) size orders

i) $S c < Y < L a$ : Atomic size increases down the group.

iii) $A l > G a < I n$ : $G a$ is smaller than $A l$ due to poor shielding by $3 d$ electrons (d-block contraction).

iv) $O^{2 -} < C l^{-}$ : $C l^{-}$ has more electron shells than $O^{2 -}$ , making it larger.

vi) $C u < Z n$ : Size increases at the end of the series ( $Z n$ ) due to strong inter-electronic repulsions in the fully filled $d^{10}$ configuration.

vii) $N i < P d \approx Pt$ : $P d$ and $Pt$ have nearly identical sizes due to the lanthanide contraction.

Chemistry - PERIODIC TABLE Question with Solution | TestHub

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