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Question
Which of the following transition metals shows +1 and +2 oxidation states?
Options
Mn
Zn
Sc
Cu
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Solution
Cu
Explanation:
Cu typically exhibits the +1 oxidation state. This is due to the fact that Cu (+1) has an electrical configuration of [Ar]3d10. It is extremely stable due to the entirely filled d-orbital. Furthermore, Cu has a +2 oxidation state.
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Reason: Ligand field effect cause distortions in crystal structures.
Transition elements form binary compounds with halogens. Which of the following elements will form \[\ce{MF3}\] type compounds?
(i) \[\ce{Cr}\]
(ii) \[\ce{Co}\]
(iii) \[\ce{Cu}\]
(iv) \[\ce{Ni}\]
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| Column I (Catalyst) | Column II (Process) |
| (i) \[\ce{Ni}\] in the presence of hydrogen | (a) Zieglar Natta catalyst |
| (ii) \[\ce{Cu2C12}\] | (b) Contact process |
| (iii) \[\ce{V2O5}\] | (c) Vegetable oil to ghee |
| (iv) Finely divided iron | (d) Sandmeyer reaction |
| (v) \[\ce{TiCl4 + Al (CH3)3}\] | (e) Haber's Process |
| (f) Decomposition of KCIO3 |
Assertion: The highest oxidation state of osmium is +8.
Reason: Osmium is a 5d-block element.
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Ionisation enthalpies
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| List-I | List-II |
| A. Haber process | I. Fe catalyst |
| B. Wacker oxidation | II. PdCl2 |
| C. Wilkinson catalyst | III. [(PPh3)3RhCl] |
| D. Ziegler catalyst | IV. TiCl4 with Al(CH3)3 |
Choose the correct answer from the options given below:
