Related InterviewSolutions

• Choose the correct statement(s) about colour of lathanoids:A. Colour of the ions may be attribued to the presence of f-electrons.B. `Lu^(3+), Yb^(2+), La^(3+), Ce^(3+)` are colourless.C. Absorption bands are narrow, probably because of excitation within f-level.D. Elements with (n) f electrons have a similar colour to those with (14-n)f electrons.
• Select the species which is an oxidant?A. `Eu^(2+)`B. `Yb^(2+)`C. `Ce^(4+)`D. `Tb^(4+)`
• Statement-1 : Lanthanoid contraction is more important than actinoid contraction is more important than actinoid contraction. Statement-2 : Chemistry of elements surrounding the actinoids are much less known at the present time.A. Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1.B. Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for Statement-1.C. Statement-1 is True, Statement-2 is falseD. Statement-1 is False and Statement-2 is True.
• Find the number of inner transition elements among those having following atomic numbers : 29, 59, 74, 95, 102, 104, 89, 57, 72.
• Identify the only paramagnetic species:A. `Ce^(4+)`B. `Yb^(2+)`C. `Lu^(3+)`D. `Nd^(3+)`
• Statement-1 : 5f orbitals resemble the 4f orbitals in their angular part of the wave-function. Statement-2 : 5f orbitals are not as buried as 4f orbitals and hence 5f electrons can participate in bonding to a far greater extent.A. Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1.B. Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for Statement-1.C. Statement-1 is True, Statement-2 is falseD. Statement-1 is False and Statement-2 is True.
• The most common oxidation states of cerium areA. `+2` and `+4`B. `+3` and `+4`C. `+3` and `+5`D. `+2` and `+3`
• Which of the following ion is paramagneticA. `La^(3+)(Z=57)`B. `Lu^(3+)(Z=71)`C. `Yb^(2+)(Z=70)`D. `Sm^(3+)(Z=62)`
• Statement-1 : `Ce^(4+)` can oxidise water. statement-2 : `Ce^(4+)` is a good analytical reagent.A. Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1.B. Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for Statement-1.C. Statement-1 is True, Statement-2 is falseD. Statement-1 is False and Statement-2 is True.
• If outermost E.C. of Ce is `4f^(1) 5d^(1) 6s^(2)`, then select the incorrectly matched outermost E.C. of its various ions in ground state:A. `Ce^(2+) rarr 4f^(1) 5d^(1)`B. `Ce^(3+) rarr 4f^(1)`C. `Ce^(4+) rarr 4f^(0)`D. `Ce^(2+) rarr 4f^(2)`