1. AS Chemistry

2. What will my lessons be like…?
3 lessons a week
1 homework a week
1 (small) test a fortnight - starts 26/9
1 (proper) test a half term
I concentrate on practical work and problem solving so you can’t just get your answers from the textbook…sorry!

3. Show of hands…
AS Re-sitters?
Triple Science?
Double Science?
Others?

4. Where are the following found…?
Protons
In the nucleus
In the shells
Attached to the quark

5. Where are the following found…?
Electrons
In the nucleus
In the shells
Attached to the quark

6. Where are the following found…?
Neutrons
In the nucleus
In the shells
Attached to the quark

7. Which of these are the…?
Atomic number (RAM)

8. Which of these are the…?
Mass number

9. Which of these are the…?
Number of electrons

10. Which of these are the…?
Number of neutrons

11. Using your periodic table calculate the number of neutrons for…
Nitrogen
Hydrogen
Chlorine

12. Using your periodic table calculate the number of neutrons for…
Nitrogen - 7
Hydrogen - 0
Chlorine - 18 or 20

13. Calculate the number of atoms and RFM for:
H2O
HCl
H2SO4
Ca(OH)2

14. Calculate the number of atoms and RFM for:
H2O 3
HCl 2
H2SO4 7
Ca(OH)2 5

15. Calculate the number of atoms and RFM for:
H2O 18
HCl
H2SO4 98
Ca(OH)2 74

16. What is the molecular formula for:
Sodium Chloride (NaCl)
Magnesium Hydroxide Mg(OH)2
Lithium Ethanoate (LiCH3COO)

17. What is the molecular formula for:
Sodium Chloride NaCl
Magnesium Hydroxide MgO2H2
Lithium Ethanoate LiC2H3O2

18. Define the term Molecular Formula…
The NUMBER and TYPE of atoms of each element in a compound

19. What is the empirical formula for:
Calcium chloride (CaCl2)
Ethanoic acid (CH3COOH)

20. What is the empirical formula for:
Calcium chloride CaCl2
Ethanoic acid CH2O

21. Define the term Empirical Formula…
The simplest WHOLE NUMBER RATIO of atoms of each element in a compound

22. How many of the following are you not expected to know…
All Half
Third None
NO Ca OH Ag V5+
CO32- Zn N NH4+ SO42-

23. How many of the following are you not expected to know…
All Half
Third None
NO Ca OH Ag V5+
CO32- Zn N NH4+ SO42-

24. ALL compounds have an overall charge of ZERO
How we calculate ionic formulae…
Remember
Metal ions LOSE electrons
Mx+
Non-metal ions GAIN electrons
NMx-
ALL compounds have an overall charge of ZERO

25. ALL compounds have an overall charge of ZERO
How we calculate ionic formulae…
The charges on an ionic compound must cancel out:
NaCl Na = 1+
Cl = 1-
NaCl = 0
ALL compounds have an overall charge of ZERO

26. ALL compounds have an overall charge of ZERO
How we calculate ionic formulae…
The charges on an ionic compound must cancel out:
CaCl2 Ca = 2+
Cl x 2 = 2 x 1-
CaCl2 = 0
ALL compounds have an overall charge of ZERO

27. Complete the ionic formulae section of the sheet…Al 3 O 2
If you are struggling, try this method

28. ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
How we calculate covalent formulae…
Remember
ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
When is this number not 8?

29. ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
How we calculate covalent formulae…
If an atom of an element is missing more than 1 electron it has two options:
Form a multiple bond
Form single bonds with more than one other atom
ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons

30. ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
How we calculate covalent formulae…
Fluorine atoms have 7 electrons in the valence shell
They require a single electron to share so Fluorine is F2
ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons

31. ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
How we calculate covalent formulae…
Fluorine atoms have 6 electrons in the valence shell
They require a pair of electron to share so can form a double bond for O2
ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons

32. ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
How we calculate covalent formulae…
Carbon requires 4 electrons
To form a compound with oxygen it needs to share 4 pairs of electrons it can do this in two ways.
ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons

33. ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
How we calculate covalent formulae…
2 oxygen atoms have 4 electrons between them allowing carbon to obtain a full valence shell as CO2
ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons

34. ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
How we calculate covalent formulae…
Carbon can also obtain a full valence shell with a single oxygen.
2 shared pairs of electrons bring the tally to 6.
The oxygen then donates a LONE PAIR to the carbon increasing its valence to 8 as CO.
ALL atoms are aiming for a COMPLETE VALENCE SHELL of electrons
Dative Covalent Bond

35. Complete the covalent formulae section of the sheet…
Remember:
The valence of H and He is 2
The valence of all other s- and p-block elements is 8
Multiple and covalent bonds are necessary in some cases

36. Let’s recap the charges on ions…
The ones you must just remember
Group 1 = +1 e.g. Li+
Group 2 = +2 e.g. Be2+
Group 3 = +3 e.g. B3+
Group 5 = -3 e.g. N3-
Group 6 = -2 e.g. O2-
Group 7 = -1 e.g. F-
The ones you need to work out
Zinc Zn +2
Silver Ag +1
Ammonium
NH4
Nitrate
NO3 -1
Carbonate
CO3 -2
Sulphate
SO4
Hydroxide OH

37. Let’s recap covalent compounds…
Single, multiple and dative bonds are possible
These prefixes apply:
Mono = one
Di = two
Tri = three
Maximum valence is 8 (or 2)

38. How do I know if it’s ionic or covalent…?
ELECTRONEGATIVITY is the ability of an atom to pull electron density towards itself.
An ionic bond forms between at least one electronegative element and one electropositive element.

39. How do I know if it’s ionic or covalent…?
Fluorine is the MOST electronegative element

40. How do I know if it’s ionic or covalent…?
Francium is the MOST electropositive element

41. Can you balance equations…?
Before you can balance an equation you need to predict the type of results!
You MUST learn these:
Acid + Metal hydroxide Salt + Water
Acid + Metal oxide Salt + Water
Acid + Metal carbonate Salt + Water Carbon Dioxide
Acid + Metal Salt + Hydrogen
Water + Metal Salt + Hydrogen

42. Text books…
Unfortunately the college is unable to buy your textbooks for you  if you feel a book would benefit you the endorsed one is:
ISBN –
(includes access to the online version)

43. Homework…
You are to research the way that the atomic model has changed from ancient Greece to the modern day.
You will undertake a task based on this research in Monday’s lesson.
Good sources of information include:
Textbooks (study centre)
Scientific blogs and journals
YouTube videos

44. The importance of numbers…
Subscript numbers show how many atoms of an element are BONDED
Prefixing number show how many of a compound is required for BALANCING

45. The importance of numbers…
Cl2 = 2 chlorines BONDED together
Mg2 = 2 magnesiums BONDED together
2Mg = 2 magnesiums required for BALANCING
MgCl2 = 1 magnesium BONDED to 2 chlorines
2MgCl2 = 2 magnesium chlorides required for BALANCING

46. Can you balance equations…?
There are a number of issues to consider when balancing equations:
Formulae of compounds
Number of atoms of an element
State symbols

47. Can you balance equations…? The FIVE steps to follow are:
Work out the expected products
Work out the formulae for all reactants and products
Balance the equations
Add in state symbols
5. CHECK!!!

48. Can you balance equations…?
Time to see if you’ve been listening. Complete the Balanced Equation activity on your sheets

49. Can you work out empirical formulae…?
Magnesium
Oxygen
RAM
0.96g g
Mass
0.96/24= /16=0.04
Moles
Molar Ratio
0.04/0.04= /0.04=1
Empirical Formula = MgO

50. Complete the empirical formulae sheet…
Element 1
Element 2
RAM
Mass
Moles
Molar Ratio
Empirical Formula = _______