Q. No.An element among the following that shows the maximum number of oxidation states is:
1. Cr
2. Fe
3. Mn
4. V
1. 3
2. 4
3. 2
4. 1
| Assertion (A): | Transition metals and their compounds are effective catalysts. |
| Reason (R): | They have the ability to adopt multiple oxidation states and to form complexes. |
Choose the correct option:
| 1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
| 3. | (A) is true but (R) is false. |
| 4. | Both (A) and (R) are false. |
Gadolinium (atomic number 64) is an element of the 4f series, Identify the correct electronic configuration of gadolinium from the following options:
\(1. (X e) 4 f^{7} 5 d^{1} 6 s^{2} \)
2. \( (X e) 4 f^{6} 5 d^{2} 6 s^{2}\)
3. \((X e) 4 f^{8} 6 d^{2}\)
4. \((X e) 4 f^{9} 5 s^{1}\)
| 1. | The extra stability of configurations such as d5, d10 |
| 2. | The less stability of configurations such as d5, d10 |
| 3. | The extra stability of configurations such as d4, d6 |
| 4. | The extra stability of configurations such as d7, d8 |
The magnetic nature of elements depends on the presence of unpaired electrons. Identify the configuration of the transition element, which shows the highest magnetic moment.
| 1. | 2. | ||
| 3. | 4. |
Which of the following is the most appropriate reason why zinc does not exhibit variable oxidation states?
1. Inert pair effect2. Completely filled 3d sub-shell.
3. Completely filled 4s sub-shell.
4. Common ion effect.
A pair of ions that have the same electronic configuration among their constituent species is:
1. \(Sr^{3+}, Cr^{3+}\)
2. \(Fe^{3+}, Mn^{2+}\)
3. \(Fe^{3+}, Co^{3+}\)
4. \(Cr^{3+}, Fe^{3+}\)
Which transition element does not exhibit variable oxidation states?
1. Manganese (\(Mn\))
2. Chromium(\(Cr\))
3. Scandium(\(Sc\))
4. Iron(\(Fe\))
| Assertion (A): | Zinc is not a transition metal. |
| Reason (R): | Zinc has a full d10 configuration in its ground state as well as in its common oxidation states. |
In light of the above statements, choose the correct answer from the options given below:
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A) |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A) |
| 3. | (A) is True but (R) is False |
| 4. | (A) is False but (R) is True |
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