Topic 1 - Atomic Structure

Question 1

Name the Particles

Answer 1

Atoms
Molecules
Ions
Electrons

Question 2

Relate speed of particles to temperature

Answer 2

Speed of particle movement is directly proportional to temperature

Question 3

Define - Atom

Answer 3

The smallest part of an element that can take part/participate in a chemical reaction because it retains the chemical properties of the element

Question 4

What is the shape of an atom?

Answer 4

• spherical - not rigid but clouded because electrons are free to move
•

Question 5

Define principle quantum number

Answer 5

Energy levels around a nucleus
All of them are quantised

Question 6

How does energy change as you move away from the nucleus?

Answer 6

The shell nearest to the nucleus has the least energy and the energy level increases as you move away from the nucleus

Question 7

What is the formula predicting the number of electrons a principal quantum number can hold?

Answer 7

2n ^2

Question 8

Describe the nucleus

Answer 8

Positively charged dense central region of an atom which is responsible for the particulate nature of the atom

Question 9

What are the different types of subshells?

Answer 9

s
p
d
f

Question 10

What is the shape of the s-subshell?

Answer 10

Spherical

Question 11

How many orbitals does the s-subshell have?

Answer 11

One

Question 12

Define - Ionisation Energy

Answer 12

Energy required to remove one mole of electrons from one mole of gaseous atoms or cations

Question 13

Define - Ionisation

Answer 13

The process of removing an electron from a gaseous atom or from a gaseous cation

Question 14

Why is Ionisation energy endothermic?

Answer 14

Energy is always needed to overcome the electrostatic force of attraction between the nucleus and the electron being removed

Question 15

Define First Ionisation energy

Answer 15

The amount of energy required to remove 1 mol of electrons from 1 mol of gaseous atoms to form 1 mol of a positively charged ion with a +1 charge

Question 16

Define Second Ionisation energy

Answer 16

The amount of energy required to remove 1 mol of electrons from a gaseous cation with charge +1 to form a positively charged cation with +2 charge

Question 17

What is the first factor that determines ionisation energy?

Answer 17

Radius - the larger the atom the lower the ionisation energy, as the valency electrons (those that are lost) are farther away from nucleus and therefore are more loosely held

Question 18

What is the trend in Ionisation energy down a group?

Answer 18

It decreases as you go down because the radius of the atoms increases

Question 19

What is the second factor determining ionisation energy?

Answer 19

Nuclear Charge
The more protons that are held by the nucleus, the greater the nuclear charge, the more strongly the electrons are held and therefore the higher the ionisation energy

Question 20

What is the trend in ionisation energy across a period?

Answer 20

I.E increases as you go across the period as the nuclear charge is also increasing
LEFT TO RIGHT

Question 21

What is the third factor determining Ionisation Energy?

Answer 21

Shielding/screening effect
This is when the electrons closer to the nucleus shield the outer electrons from the nucleus, (repulsion) making them easier to lose as they are farther from the nucleus and held more loosely

Question 22

Evidence of the existence of shells

Answer 22

Successive I.E of one element
The big jumps if they were plotted on a graph show how many shells there are

Question 23

Evidence for the existence of subshells

Answer 23

The first ionisation energy of successive elements

Question 24

Define - Effective Nuclear Charge

Answer 24

The amount of nuclear charge that manages to reach the outer shell and stay there

Question 25

How many orbitals does the p sub-shell have?

Answer 25

Three
Nucleus at the node of the dumbell

Question 26

How many orbitals does the d subshell have?

Answer 26

Five
10 electrons held

Question 27

Define

Degenerate orbitals

Answer 27

orbitals that are at the same energy level

electrons can slide between the orbitals

Question 28

Define

Half filled stability

Answer 28

When a subshell is half filled it means it is experiencing minimal repulsion and is therefore more stable

Question 29

Define

Full filled stability

Answer 29

When a subshell is fully filled it has extra electronic stability

Question 30

Why does Boron have a lower first IE than expected?

Answer 30

The first electron is removed from a P orbital which is farther away from the nucleus and more shielded (less strongly held)

Question 31

Why does Beryllium
have a higher first IE than expected?

Answer 31

First electron to be removed from an s subshell with a pair and more energy is needed to over come the strong forces of attraction between the electrons with opposite spins

Question 32

Why does Phosphorus have a higher first IE than expected?

Answer 32

First electron is removed from a half filled sub-shell, where orbitals occupy the space singly, experience minimal repulsion (half filled stability)

Question 33

Why does sulphur have a lower first IE than expected?

Answer 33

First electron is removed from an orbital that has a pair where the electrons experience spin-spin repulsion

Question 34

Why does sulphur have a lower first IE than expected?

Answer 34

First electron is removed from an orbital that has a pair where the electrons experience spin-spin repulsion