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Question
Which of the following characteristics of transition metals is associated with their catalytic activity?
Options
Paramagnetic nature
Colour of hydrated ions
High enthalpy of atomisation
Variable oxidation states
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Solution
Variable oxidation states
Explanation:
Transition metals have a tendency to have varying oxidation states, which allows them to create unstable intermediates and provide a novel reaction path with a lower Ea. As a result, transition metals have catalytic activity.
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| Column I (Aqueous solution of salt) |
Column II (Colour) |
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| (ii) \[\ce{NiCl2.4H2O}\] | (b) Light pink |
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| (iv) \[\ce{CoC12,6H2O}\] | (d) Pale green |
| (v) \[\ce{Cu2 Cl2}\] | (e) Pink |
| (f) Colourless |
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