2A - Atoms & Redox

Question 1

6 rules for oxidation numbers?

What rules apply to what?

Answer 1

1 - Atoms of uncombined elements = 0

2 - Atoms of Group 1 element = +1

3 - Atoms of Group 2 element = +2

4 - Fluorine atoms = -1

5 - Oxygen atoms = -2 expect when it’s a peroxide then it’s -1 e.g. H₂O₂

6 - Hydrogen atoms = +1 expect wen they’re in a hydride then they’re -1 e.g. LiH

Rule 2 onwards apply to atoms of combined elements in compounds.

Question 2

3 factors that affect the amount of energy required to remove an outer electron

Answer 2

• Distance from nucleus
• Charge on nucleus
• Number of electrons in previous shell (electron shielding)

Question 3

What does a mass spectrometer do?

How are the deflected ions displayed?

Answer 3

• Measures the percentage abundance of an isotope
• Mass to charge ratio: m/z

Question 4

How to work out the relative abundance of each isotope from the graph of a mass spectrometer experiment?

Answer 4

Abundance of each isotope = height of the the isotope bar / Total height of all the bars

Question 5

4 steps of the mass spectrometer

Answer 5

1 - Ionisation

2 - Acceleration

3 - Deflection

4 - Detection