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solid state 12th cet mc

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MHT-CET 2015 Q1. Select a ferromagnetic material from the following. (A) Dioxygen (B) Chromium(IV) oxide (C) Benzene (D) Dihydrogen monoxide Show Solution Correct Answer (B) Chromium(IV) oxide Detailed Explanation: Ferromagnetism: Substances that show permanent magnetism even when the external magnetic field is removed. This occurs due to the spontaneous alignment of magnetic moments (domains) in the same direction. While metals like Iron (Fe), Cobalt (Co), and Nickel (Ni) are classic examples, Chromium(IV) oxide (CrO 2 ) is a unique metallic oxide. Because of its strong ferromagnetic properties, it was historically the standard material used in high-fidelity magnetic recording tapes (cassettes). ...
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7. Elements of group 16,17,18 12

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MHT-CET MCQ Practice Elements of group 16, 17, 18 CET MCQ Chemistry | MHT-CET Previous year questions with detailed solutions MHT-CET 2014 Q1. What is the geometry of a molecule of bromine pentafluoride? (A) Square planar (B) Trigonal bipyramidal (C) Square pyramidal (D) Octahedral Solution: In BrF 5 , the central Bromine atom has 7 valence electrons. It forms 5 sigma bonds with 5 Fluorine atoms. Number of lone pairs = (7 - 5) / 2 = 1 lone pair. Total electron pairs (Steric Number) = 5 (bond pairs) + 1 (lone pair) = 6. The hybridization is sp 3 d 2 . According to VSEPR theory, 6 electron pairs with 1 lone pair results ...
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8. Transition and inner transition element 12th chem CET MCQ

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[2013] 1. Which of the following ion is diamagnetic? (A) Sc 3+ (B) Ni 2+ (C) V 3+ (D) Fe 2+ Correct Answer: (A) Sc 3+ Solution: Sc (Z=21) has the configuration [Ar] 3d¹ 4s². In the +3 oxidation state, it loses 3 electrons to become [Ar] 3d⁰. Since there are no unpaired electrons, it is diamagnetic[cite: 10]. [2014] 2. Select the coloured compound amongst the following. (Atomic no. Ti=22, Cr=24 Cu=29, Zn=30) (A) TiCl 4 (B) CrCl 3 (C) ZnCl 2 (D) CuCl Correct Answer: (B) CrCl 3 Solution: Colour in transition metal compounds is due to d-d transitions[cite: 20]. Cr³⁺ (3d³) has unpaired electrons, making it coloured[cite: 30]. Ti⁴⁺ (3d⁰), Zn²⁺ (3d¹⁰), and Cu⁺ (3d¹⁰) do not have unpaired electrons in the d-subshell. ...
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