Which of the following is / are incorrectly matched. (i) Be + 2 He Br → IE 1 order (ii) Une element belongs to → 7 th period 9 th group (iii) Li + Mg 2 + Al 3 + Be 2 + → Ionic radius order

Question

Which of the following is / are incorrectly matched.

(i) $Be^{+ 2} > He > Br \to IE_{1}$ order

(ii) Une element belongs to $\to 7^{th}$ period $9^{th}$ group

(iii) $Li^{+} > Mg^{2 +} > Al^{3 +} > Be^{2 +} \to$ Ionic radius order

(iv) $Cu < Zn \to IE_{2}$ order

(v) $S < Cl > F \to$ EA order

(vi) $CrO < Cr_{2} O_{3} < CrO_{3} \to$ Acidic strength order

(vii) $Li^{+}_{(qa)} < Na^{+}_{(qa)} < K^{+}_{(qa)} \to$ Ionic mobility order

(viii) $F^{-} < Cl^{-} < Br^{-} < H^{-} < I^{-} <^{-} \to$ Ionic radius order

TestHub · Accepted Answer

Statement (iv) is wrong: The second ionization energy ( $I E_{2}$ ) of Cu is greater than Zn ( $C u > Z n$ ) because removing an electron from Cu $^{+}$ ( $3 d^{10}$ ) requires breaking a highly stable, fully-filled d-subshell, whereas Zn $^{+}$ ( $3 d^{10} 4 s^{1}$ ) easily loses its remaining 4s electron.

All other statements are correct: (i) follows the effective nuclear charge and stable configurations; (ii) Une ( $Z = 109$ ) sits in period 7, group 9; (iii) follows ionic size trends; (v) Cl has the highest electron affinity due to low repulsion; (vi) acidity increases with higher oxidation states ( $+ 2 < + 3 < + 6$ ); (vii) smaller ions hydrate more, reducing mobility; (viii) H $^{-}$ has a surprisingly large radius due to low nuclear charge.

Conclusion: Only 1 statement is incorrectly matched (Answer: 1.00)

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