Topic 1: Atomic Structure and the Periodic Table

Question 1

What 3 particles are atoms made out of?

Answer 1

Protons, neutrons & electrons

Question 2

Describe the properties of protons, neutrons and electrons in terms of relative charge and relative mass.

Answer 2

Protons - mass- 1, relative charge +1
Neutrons - mass - 1, relative charge 0
Electrons, -mass 1/2000, relative charge-1

Question 3

Define atomic number

Answer 3

number of protons in nucleus of an atom - it defines the element

Question 4

Define mass number

Answer 4

The number of protons and electrons in the nucleus of an atom

Question 5

How do atoms form ions?

Answer 5

Atoms form ions by gaining or losing electrons.

Question 6

Define Isotope

Answer 6

Isotopes of an element are atoms with the same number of protons but different number of neutrons.

Question 7

Define relative isotopic mass

Answer 7

The mass of an atom of an isotope of an element divided by 1/12 carbon-12 atom.

Question 8

Define relative atomic mass

Answer 8

The average mass of an atom of an element divided by 1/12 of a carbon-12 atom

Question 9

Same electronic configuration means…

Answer 9

same chemical properties

Question 10

An atom is defined by the number of protons

Answer 10

same protons = same element

Question 11

What is mass spectrometry?

Answer 11

A method to accurately determine the masses of atoms or molecules. Can give vital information about the structure of a molecule or the abundance of isotopes.

Question 12

Describe the

Answer 12

-

Question 13

Energy levels (shells) –> subshells –> orbitals

*name the four types of orbitals and describe their shape and the max number of electrons they can hold

Answer 13

1. s-orbitals - spherical (max 2)
2. p-orbitals - dumbell shaped (max 6)
   (3 p-orbitals)
3. d- orbitals (max 10)
4. f-orbitals (max 14)

Question 14

Name the 3 ways electron configuration can be presented

Answer 14

1. Sub-shell notation
2. Arrows in boxes
3. Energy level diagrams

Question 15

Define first ionisation energy

Answer 15

The energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions (kj/mol) - Endothermic

Question 16

*** Do not forget STATE SYMBOLS when writing equations for ionisation energies

Answer 16

1st - A(g) —> A+ (g) + e-

2nd - A(g)+ —> A2+ (g) + e-

Question 17

Define successive ionisation energies

Answer 17

You can remove all electrons from an atom leaving only the nucleus. Each time you remove an electron, theres a successive ionisation energy

Question 18

What are the three factors affecting the first ionisation energy?

Answer 18

1. Nuclear Charge
2. Shielding
3. Atomic radius

Question 19

Describe nuclear charge

**How does this affect ionisation energy?

Answer 19

Electrostatic attraction
The force of attraction experienced by the electrons due to the nucleus.
**As the number of protons increase the nuclear charge increases - force of attraction experiences by outer electrons is greater SO ionisation energy increases.

Question 20

Describe shielding

**How does this affect ionisation energy?

Answer 20

** Nuclear charge experienced by outer electrons decreases as more electrons are added.
Happens as any group is descended…

Question 21

Describe atomic radius

**How does this affect ionisation energy?

Answer 21

** As atomic radius increases; outer electrons become further away from attractive force of nucleus SO less energy is required to remove electrons

Question 22

Define isoelectronic

Answer 22

elements with the same electronic configuration

Question 23

What is the general trend in the first ionisation energy across a period?

Answer 23

as you move across —> Ionisation energies increase

*number of protons increasing - nuclear attraction

Question 24

What is the general trend in the first ionisation energy down a group?

Answer 24

as you move down a group —-> Ionisation energy decreases