Topic 1- Atomic Structure

Question 1

What is an ion?

Answer 1

Have a different number of electrons and protons

Question 2

What is an isotope?

Answer 2

Elements with the same number of protons but different number of neutrons!

Question 3

What is Relative Atomic Mass

Answer 3

Average mass of an atom of an element when measured on scale on which the mass of 12C is exactly 12.

Question 4

What is Relative Molecular Mass?

Answer 4

Average mass of a molecule when measured on scale on which the mass of 12C is exactly 12.

Question 5

What is Relative Isotopic Mass?

Answer 5

The mass of an isotope of an element measured on scale on which the mass of an atom of 12C is exactly 12.

Question 6

Time of Flight Mass Spectrometry.

Answer 6

1. Vaporisation
So it can travel through the mass spectrometer.
2. Ionisation
-Electrospray
-Sample pushed through a nozzle making a high pressure jet.
-Causes a loss of electrons
-A gaseous positively charged sample is produced.
-E.g: P + H^+ -) PH^+
3. Acceleration
-Positive ions passed through an electric field.
-Particles with lower mass/charge ratio will be a lot quicker.
4. Ion Drift
- Particles travel with constant speed and Ke.
5. Detection
-Ions are detected as electrical current is made when particle hits the plate.

Question 7

What is Ionisation?

Answer 7

The minim amount of energy required to remove 1 mole of electrons from 1 mole of atoms in gaseous state.
Example:
Na(g) -) Na^+(g)+e^-

Question 8

Shielding

Answer 8

-More electron shells between the positive nucleus and the negative electron that is being removed, less energy is required to remove the outer electron. Due to a weaker attractive.

Question 9

Atomic Size

Answer 9

-Bigger atom, further away outer electron are from the nucleus.
-Attractive forces between nucleus and outer electron reduces.
-Therefore easier to remove an electron.

Question 10

Nuclear Charge

Answer 10

-More protons in the nucleus the high the attraction between nucleus and outer electron.
-More energy required to remove the electron.

Question 11

1st Ionisation trend- Group

Answer 11

-Decreases down a group
-Atomic radius increases down a group.
-Outer electron further from the nucleus.
-Attractive force is weaker therefore easier to remove an electron!
-Shields increase down a group. More shells between nucleus and outer shell.
Due to weaker force it is easier to remove an electron.

Question 12

1st Ionisation trend- Periods

Answer 12

-Increases across a period.
-More proton in a nucleus therefore an increased nuclear attraction.
-More energy required to remove an electron.