Advertisements
Advertisements
Question
While filling up of electrons in the atomic orbitals, the 4s orbital is filled before the 3d orbital but reverse happens during the ionisation of the atom. Explain why?
Advertisements
Solution
Electrons are filled to the n + l rule. If an orbital has lower n + l value, then the electron will enter that orbital.
For 3d, n + l = 3 + 2 = 5
4s, n + l = 4 + 0 = 4
So, the electron will first enter 4s and then 3d while filling. But, 4s electrons are held loose by the nucleus and are outside of 3d, so removing a 4s electron becomes easier than removing a 3d electron.
APPEARS IN
RELATED QUESTIONS
Explain why is Fe3+ more stable than Fe2+?
What are the transition elements? Write two characteristics of the transition elements.
In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomization of zinc is the lowest, i.e., 126 kJ mol−1. Why?
Calculate the ‘spin only’ magnetic moment of \[\ce{M^{2+}_{ (aq)}}\] ion (Z = 27).
NF3 is possible, but NF5 is not. Why?
An analysis shows that FeO has a non-stoichiometric composition with formula Fe0.95O. Give reason.
The transition metals show _________ character because of the presence of unpaired· electrons and Cu+ is ____________ because of its electronic configuration is [Ar]3d10
Explain why transition elements form alloys.
Maximum magnetic moment is shown by ____________.
The magnetic moment is associated with its spin angular momentum and orbital angular momentum. Spin only magnetic moment value of \[\ce{Cr^{3+}}\] ion is ______.
Explain why does colour of KMnO4 disappear when oxalic acid is added to its solution in acidic medium.
Assertion: \[\ce{Cu^2+}\] iodide is not known.
Reason: \[\ce{Cu^2+}\] oxidises \[\ce{I^-}\] to iodine.
If enthalpies of formation of C2H4(g), CO2(g) and H2O(l) at 25°C and 1 atm pressure are 52, – 394 and – 286 kJ/mol respectively, the change in ethalpy for combustion of C2H4 is equal to
Which of the following species has maximum magnetic momentum?
Give reason for the following statement:
[Ti(H2O)]3+ is coloured while [Sc(H2O)6]3+ is colourless.
In the ground state of atomic Fe (Z = 26), the spin-only magnetic moment is ______ × 10-1 BM.
(Round off to the nearest integer).
[Given: `sqrt3 = 1.73, sqrt2 = 1.41`]
Which property of transition metals enables them to behave as catalysts?
A pair of coloured ions is ______.
Give a reason for the following:
Transition metals possess a great tendency to form complex compounds.
Decide which of the following atomic numbers are the atomic numbers of the inner transition elements:
29, 59, 74, 95, 102, 104
