Orbitals / Trends / Rules

Trends

100

Across a period, electronegativity increases

True/False

True, remember the electronegativity of Na is weaker than F

200

Define isoelectronic species and give an example with 3 atoms

Atoms with the same charge (number of electrons), eg O2- F- Na+

300

Are cations or anions LARGER than the parent atom?

Anions are larger

- ENC (effective nuclear charge) decreases

- Pull is weaker 

- Atoms is larger

400

Draw on the sample periodic table

- Atomic radius trend

- Electron affinity trend

- Metallic character trend

- AR (bottom left)

- EA (top right)

- MC (bottom left)

Rules

300

XYZ = No two electrons can have the same 4 quantum numbers

What is XYZ?

Pauli's Exclusion Principle

400

Aufbau's principle states in excitation, electrons fill atomic orbitals of the lowest available energy levels before higher levels

True/False

False. At ground state electrons...

500

Describe Hund's Rule and give an example of an exception (with its electron subshell configuration)

- Electrons singly fill up orbitals of the same level before pairing up

- Each singly orbital has parallel spin

Shapes/Nodes

100

# (number of radial nodes) = n - l - 2

True/false?

False. n-l-1 will give you the number of radial nodes

n - principle number

l - angular momentum number

200

What orbital often corresponds with a cloverleaf shape?

d orbitals

300

Orbital Size is not definitively determinable. A boundary surface of 99% is used for calculations

True/False

False, 90% boundary is used

400

Angular nodes are only dependent on what orbital you have (eg s,p,d,f)

True/false?

True, s = 0 angular node

p = 1 angular node

d = 2

f = 3

500

What are angular nodes (nodal plane)?

Planes or cones passing through the nucleus where the angular wavefunction is 0

Definitions T/F

100

A node is a point where phases change

True/False

True, Nodes are where phases change (go from positive to negative or vice versa)

Wavefunction is zero at nodes

300

Energetically degenerate refers to orbitals with the same energy.

True or False?

True

400

For Bromine (35), which has an electron subshell config of [Ar] 4s2 3d10 4p5...

... 4p5 represents the valence electrons

True/False

False, 4s2 and 4p5 represent the valence electrons.

[Ar] and 3d10 represent the core electrons