Atoms and elements

What are s- orbitals?

S-orbitals have a spherical contour surface because the wave function is spherical -symmetrical.

With increasing n the s-orbitals become bigger

With increasing n the number of nodes increases

What are p-orbitals?

Dumbbell shaped (different lobes have opposite signs (+/-) for opposite directions - but identical probability!

• One node each through the nucleus

• 3 possible orientations (px, py, pz)

• Orbitals show identical (degenerate) energy

What are d-orbitals?

• Leaf-clover shaped; the four orbital lobes have opposite signs (+/-) – the fith looks like a floating tyre

• Two nodes through the nucleus

• 5 possible orientations (dxy, dyz, dzx dx2-y2,dz2)

• d-Orbitals are particularely important in transition metals

What are f-orbitals?

• Complex geometry

• Three nodes through the nucleus

• 7 possible orientations

• f-Orbitals are particularely important in lanthanois and actinoids

Do the contour plot of the s-orbitals

60 (page)

Plot the solutions of Schrödinger equaion of the s-orbital

61 (page)

Do the countour plot of the p-orbital

62 (page)

Do the contour plot of the d-orbital

63(page)

Do the contour plot of the f-orbital

64 (page)

What are the possibile orientations of the f-orbitals?

z*3

xz*2

yz*2

xyz

z(x*2-y*2)

x(x*2-3y*2)

y(y*2-3x*2)

Plot the atomic orbitals

65 ( page)

What is the relationship between the principal quantum number (n) and the number of subshells?

The shell with principal quantum number n contains exactly n subshells.

How many orbitals does each subshell have?

Each subshell consists of  2l + 1  orbitals, corresponding to the allowed values of  m_l , ranging from -l to +l.

What is the total number of orbitals in a shell with quantum number n ?

The total number of orbitals in a shell is  n^2 .

How does the principal quantum number n relate to the angular momentum quantum number l ?

For a shell with principal quantum number  n , the possible values of  l  range from  0  to  n - 1 .

How much electrons can each orbital hold?

A maximum of two electrons

How do electrons behave?

They spin around their own axis

Which quantum number do atoms need when they have more electrons

ms

What is the purpose of the quantum number  m_s ?

Describes the intrinsic spin of the electron and the direction of its magnetic field.

State the Pauli Exclusion Principle.

No two electrons in the same atom can have identical sets of quantum numbers.

Electrons within the same orbitals must have different spins.

How can the energy of each orbital be calculated?

From wave function and quantum numbers

How are the energies of the orbitals (s,p,d and f) with the same principal quantum number of atoms that can hold more electrons?

They are not degenerate

What is Hund’s Rule?

Electrons fill degenerate orbitals singly with parallel spins before pairing up.

What is the electron configuration?

That is the listing of all occupied orbitals with the number of electrons in each orbital