The +2 oxidation state becomes more stable in the first half of the first-row transition elements with increasing atomic number because:
1. | s-Orbital is becoming more and more half-filled. |
2. | f-Orbital is becoming more and more half-filled. |
3. | d-Orbital is becoming more and more half-filled. |
4. | p-Orbital is becoming more and more half-filled. |
The oxo metal anions of the 3d series in which the metal exhibits an oxidation state equal to its group number is /are -
1. | 2. | ||
3. | 4. | All of these |
The consequence(s) of lanthanoid contraction is/are :
1. | Similarity in the properties of second and third transition series. |
2. | Separation of lanthanoids is difficult. |
3. | Variation in the basic strength of lanthanide hydroxides. |
4. | All of the above. |
The d-block elements that may not be regarded as transition elements are :
1. | Mn, Fe, Ni because these have partially filled d-subshell. |
2. | Mn, Fe, Ni because these have completely filled d-subshell. |
3. | Zn, Cd, and Hg because these have completely filled d-subshell. |
4. | Zn, Cd, and Hg because these have partially filled d-subshell. |
What is the electronic configuration of transition elements?
1. | \((n-1) d^{1-10} n s^{0-2} \) | 2. | \((n-1) d^{1-10} n s^2 \) |
3. | \(n f^2~ n p^{1-6} \) | 4. | \(n d^2~ n p^{1-6}\) |
The different oxidation states exhibited by the lanthanoids are:
1. | +2, -3, +4 | 2. | -2, -3, -4 |
3. | +2, +3, -4 | 4. | +2, +3, +4 |
The "Disproportionation" reaction means that :
1. | A relatively less stable oxidation state undergoes an oxidation−reduction reaction. |
2. | A relatively more stable oxidation state undergoes an oxidation−reduction reaction. |
3. | A relatively less stable oxidation state undergoes a hydrogenation reaction. |
4. | A relatively more stable oxidation state undergoes a hydrogenation reaction. |
In the 3d series, a metal with a +1 oxidation state is:
1. | Mn | 2. | Cu |
3. | Fe | 4. | Zn |
The number of unpaired electrons in the gaseous ions are, respectively:
1. | 3, 2, 3, and 1 | 2. | 2, 2, 3, and 1 |
3. | 4, 3, 2, and 1 | 4. | 1, 2, 3, and 4 |
Alloy that contains lanthanoid metals is-
1. | Mischmetal
|
2. | Permalloy
|
3. | Supermalloy
|
4. | Brass |