Topic B: Atomic Structure

Question 1

What are all sub-levels in order?

Answer 1

s,p,d,f

Question 1

What do sub-levels contain?

Answer 1

Each sub-level contains a fixed number of orbitals

Question 2

What are orbitals?

Answer 2

Orbitals are regions of space with a high probability of finding an electron
Each orbital can hold a maximum of 2 electrons

Question 3

What are the number of orbitals in each of the 4 sub-levels?

Answer 3

s: 1
p: 3
d: 5
f: 7

Question 4

What is the energy of the orbitals dependent on?

Answer 4

Nuclear charge
Other electrons present in the atom
- Attraction between electrons and nucleas
- Repulsion between electrons

Question 5

When is an electron in an atom considered stable?

Answer 5

When the total attractive interactions are greater than the total repulsive interactions

Question 6

What is the size of an s orbital?

Answer 6

Spherical, non-directional

Question 7

What happens to the orbital when the principal quantum number increases

Answer 7

The size of the orbital increases

Question 8

What is the shape of a p orbital

Answer 8

Dumbell, directional

Question 9

How do the different orbitals in each sub-level differ from each other?

Answer 9

The different orbitals in each sub-level have different directions in space, with the exception of the s orbital, as it is non-directional

Question 10

How are electrons added to empty orbitals

Answer 10

Electrons are added progressively starting with the lowest energy.

Question 11

How are electrons removed from filled orbitals

Answer 11

Electrons are removed progressively starting with the lowest energy

Question 12

What is the Pauli expulsion principle

Answer 12

Paired electrons in an orbital can only be stable when they spin in opposite directions

Question 13

What is Hund’s rule

Answer 13

When filling a sublevel with electrons, each orbital must be filled singly with one electron before they are occupied in pairs

Question 14

What does each value mean in the following notation for writing electron configuration:
2p’

Answer 14

2: main energy level
p: sub-level
1: number of electrons in sub-level

Question 15

What are the 2 exceptions to the Aufbau principal and why are they exceptions

Answer 15

Chromium and Copper. Chromium and copper have 5 and 10 electrons in the 3d orbital instead of the expected 4 and 9. The reason is that fully-filled and half-filled orbitals are extra stable

Question 16

Where are electrons lost from when forming cations

Answer 16

Electrons are lost from the orbital with the highest energy

Question 17

Where are electrons taken from when forming anions

Answer 17

Electrons are taken from the vacant orbital with the highest energy