1. Cumulative Exam Review
Q-mew-lah-t’v

2. List of topics on the exam
Periodic table elements 1 – 20 (you will receive a periodic table with your exam)
Subatomic particles – proton, neutron, electron
Energy levels
Covalent bonds
Ions and ionic bonds
Types of reactions
Experimental design
Variables – Independent, dependent, controlled
Organizing and graphing results of an experiment

3. Chemistry is the study of the composition, structure, and properties of matter. All matter is made of atoms.
All atoms are made of:
amu = atomic mass units.
Always show units!
Sub-atomic particle
Charge
Location
Mass (amu)
Proton
1.01
Neutron
Electron
Positive +
Nucleus 🚫🚫
Neutral
Nucleus
Negative —
Energy levels
You can use the words to help you remember which goes with which!
Electrons are way smaller than protons and neutrons

4. Reading the periodic table1
Atomic number
What does the atomic number tell you?
The number of protons and electrons
1.01
Symbol
The name of the element Li 3 Be 4
Atomic mass
How heavy one atom of the element is
6.94
9.01 Na 11 Mg 12
22.98
24.30

5. Reading the periodic table
Why does helium have 2, not 8 electrons in the outside energy level?
Column 1 2 3 4 5 6 7 8
What does the column number tell us?
The number of electrons in the outside energy level

6. + + + + + + + + — — — 🚫🚫 🚫🚫 🚫🚫 🚫🚫 🚫🚫 🚫🚫 — — 🚫🚫 🚫🚫 — — —
Assuming we can see all the particles in this nucleus, which element is this? — —
Oxygen —
How many electrons does this element have? 🚫🚫 🚫🚫 + 🚫🚫
Eight, the same number as protons 🚫🚫 + 🚫🚫 + + — 🚫🚫 — +
What is the net charge of this atom? + + + 🚫🚫 🚫🚫
Neutral, because (+8) + (-8) = 0 — — —

7. Atoms are most stable when they have a full outside energy level— — — —
How many electrons need to be added to make the outside ring full? 🚫🚫 🚫🚫 + 🚫🚫 🚫🚫 + 🚫🚫 + +
2. The capacity goes 2, 8, 8 — + 🚫🚫 — + +
An ion is an atom with a different number of electrons and protons. What is the net charge of this ion? + 🚫🚫 🚫🚫 — — —
-2, because = -2
8 protons (positives) with 10 electrons (negatives) —

8. Sometimes, the easiest way to get a “full” energy level is to empty one.—
How many electrons need to be added? How many removed? 🚫🚫 🚫🚫 +
6 added, 2 removed. It is easier to remove 2, so that is favoured. 🚫🚫 + — 🚫🚫 — + +
What is the net charge of this beryllium ion? 🚫🚫
+2, because (+4) + (-2) = 0
4 protons (positives) with 2 electrons (negatives) —

9. Ionic charge quiz
What is the net charge of an ion for each of the following atoms? 1. F 2. N 3. Ca 4. K 5. Ar
Argon already has a full outside energy level, it is does form ions!
Answers:

10. Ionic bonds
What happens when one molecule that adds electrons to form an ion meets a molecule that loses electrons to form an ion?
No, thank you!
Thank you! +2 -2 Mg O

11. Ionic bonds
What happens when one molecule that adds electrons to form an ion meets a molecule that loses electrons to form an ion? The same thing that happens when a positive magnet meets a negative magnet: +2 -2 Mg O

12. Ionic bonds quiz
How many of each atom are needed to form the following ionic compounds:
1. Potassium chloride – K x Cl y
2. Calcium oxide – Ca x O y
3. Magnesium chloride – Mg x Cl y
4. Potassium sulfide – K x S y
5. Aluminum Oxide – Al x O y
1. KCl 2. CaO 3. MgCl2 4. K2S 5. Al2O3
Answers:

13. Another way to make full energy levels is by covalent bonding
Why are there 4 dots around the carbon? Why not 6 or 8?
To make a molecule CHx, how many hydrogens are necessary?
There are 4 electrons in the outside energy level of carbon.
Hydrogen has one electron to offer, carbon needs 4 electrons, so 4 hydrogens. C H H H H

14. Another way to make full energy levels is by covalent bonding
Any electron in a circle belongs to that atom.
Carbon almost always forms covalent bonds. C H H H H

15. Covalent bonds quiz
Draw the covalent bonds for the following molecules: 1. Hydrogen gas – H2 2. Dihydrogen monoxide – H2O 3. Ozone – O3 (hint: triangle) 4. Propane – CH3-CH2-CH3 5. Potassium hydroxide – KOH ← This one uses a covalent and an ionic bond!