JEE Main 2020 · ChemistryMultiple choiceSingle correctMediumApplication

JEE Main 3 September 2020, Shift 2, Chemistry Q37

Question 37 of 75 in this shift, Chemistry question 12 of 25.

The d-electron configuration of

\mathrm{[Ru(en)_3]Cl_2}

and

\mathrm{[Fe(H_2O)_6]Cl_2}

, respectively are :

(1) $t_{2g}^4\ e_g^2$ and $t_{2g}^4\ e_g^2$
(2) $t_{2g}^6\ e_g^0$ and $t_{2g}^6\ e_g^0$
(3) $t_{2g}^4\ e_g^2$ and $t_{2g}^6\ e_g^0$
(4) $t_{2g}^6\ e_g^0$ and $t_{2g}^4\ e_g^2$ Official answer

Official answer

Option 4

NTA final key (Sep 2020).

Chapter: Coordination Compounds
Topic: Crystal Field Theory
Idea tested: High and Low Spin States

Same idea in other shifts

Asked 34× in all

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5 Apr 2026, Shift 2 · Q71The total number of unpaired electrons present in the $d^3$ , $d^4$ (low spin) $d^5$ (high spin), $d^6$ (high spin) and $d^7$ (low spin)…EasyNumerical value
6 Apr 2026, Shift 2 · Q61Which of the following sequences of hybridisation, geometry and magnetic nature are correct for the given coordination compounds ? A.…MediumOther
8 Apr 2026, Shift 2 · Q71Number of paramagnetic complexes among the following is ________. $[\mathrm{MnBr_4}]^{2-}$ , $[\mathrm{NiCl_4}]^{2-}$ ,…MediumNumerical value
2 Apr 2025, Shift 1 · Q60Given below are two statements : Statement (I) : In octahedral complexes, when $\Delta_o<$ P high spin complexes are formed. When…EasyTwo statements
2 Apr 2025, Shift 1 · Q74A transition metal (M) among Mn, Cr, Co and Fe has the highest standard electrode potential ( $\mathrm{M^{3+}/M^{2+}}$ ). It forms a metal…MediumNumerical value
2 Apr 2025, Shift 2 · Q61The type of hybridization and the magnetic property of $\mathrm{[MnCl_6]^{3-}}$ are,MediumSingle correct
3 Apr 2025, Shift 2 · Q62Identify the diamagnetic octahedral complex ions from below ; A. $[\mathrm{Mn(CN)_6}]^{3-}$ B. $[\mathrm{Co(NH_3)_6}]^{3+}$ C.…MediumOther

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.