Mn2+ compounds are more stable than Fe2+ compounds towards oxidation in their +3 state because :
|1.||3d5 configuration is more stable than 3d6 configuration.|
|2.||3d6 configuration is more stable than 3d5 configuration.|
|3.||3p5 configuration is less stable than 3p6 configuration.|
|4.||3p6 configuration is less stable than 3p5 configuration.|
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 -
4. All of the above.
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)d1-10 ns0-2
2. (n − 1)d1-10 ns2
3. nf2 np1-6
4. nd2 np1-6
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:
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|