Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physical Chem (AS) > 1.1 Atomic Structure > Flashcards

1.1 Atomic Structure Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

Describe the Plum Pludding model

J.J Thompson

A
  • Sphere of positive charge
  • small negative charges distributed evenly throughout it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the electron shell model

A
  • Small, dense central nucleus
  • surrounded by orbiting electrons in electron shells

discovered by rutherford

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define Relative atomic mass

A

Mean mass of an atom of an element, divided by one twelfth of the mean mass of an atom of the carbon-12 isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define an isotope

A
  • Atoms of the same element
  • Same Atomic Number
  • Different Mass number
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do isotopes have different between each other

A

Different physical properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How are ions formed

A
  • When an atom loses / gains an electron
  • no longer neutral
  • will have an overall charge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is mass spec used for

A
  • Analytical technique
  • to identify diff isotopes
  • to find overall atomic mass of element
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does TOF mass spec work

A
  • Records time it takes for iones of each isotope to reach a detector
  • Produces spectra to show each present isotope
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Name the five stages of TOF mass spec

A
  1. Ionisation
  2. Acceleration
  3. Ion Drift
  4. Detection
  5. Analysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe and Explain how TOF Mass spec works

A
  • Ionisation
    Sample is vaporised + injected into spectrometer where high voltage passed over chamber. This removes 1 electron, ionising
  • Acceleration
    Ions are accelerated towards negatively charged detection plate
  • Ion Drift
    Ions are deflected by a magnetic field into a curved path.
  • Detection
    Ions hit the plate, gaining electron, producing flow of charge. Greater abundance = greater charge
  • Analysis
    Current values used in combination with flght times to produce spectra, with relative abundance of each isotope
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does the radius of ions’ path during ion drift in TOF mass spec dependant on?

A

Charge and Mass of the ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens to the m/z ratio, when a 2+ ion is produced

A

The m/z ratio is halved, and can be seen on the spectra as a trace at half the expected m/z value

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How many electrons can each orbital hold

A
  • S-orbital = 2 electrons
  • P-orbital = 6 electrons
  • D-orbital = 10 electrons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does energy change from orbitals s-d

A

Energy increases across orbitals s-d, meaning orbitals filled in this order.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Explain electron spin pairing

A
  • electrons pair up with oppsoite spin
  • to make the atom stable
  • atoms in same orbital must have opposite spin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does electron spins that are unpaired produced

A

Natural repulsion

17
Q

Explain natural repulsion

A
  • Electron spins are unpaired and unbalanced
  • atom is very unstable
  • electrons may take on a diff arrangement to improve stability
18
Q

Define ionisation energy

A

The minimum energy required to remove one mole of electrons from one mole of stoms in a gaseous state. it is measured in kJmol-1

19
Q

Explain successive ionisation energies

A
  • Further electrons removed
  • requires more energy to remove
  • electrostatic attraction increases as atomic radius decreases
  • eneergy needed to overcome this attraction
  • ionisation energy increases
20
Q

Explain the trend in first ionisation energy along a period

A
  • Ie increases
  • decreasing atomic radius
  • greater electrostatic force of attraction
21
Q

Explain the trend in first ionisation energy down a group

A
  • Ie decreases
  • increasing atomic radius
  • shielding
  • reduces electrostatic forces of attraction
22
Q

How does Ionisation energy change as you take it from the next orbital

A
  • sudden increase in Ie
  • electron removed from orbital closer to nucleus
  • more electrostatic attraction
  • therefore more energy requuired
23
Q

Explain the first ionisation energy of aluminium

(it drops)

A
  • lower than expected
  • single pair of electrons with opposite spin
  • natural repulsion
  • easier removal
  • reduces the amount of energy needed to remove

Physical Chem (AS) (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions