Download Cumulative Exam Review

Cumulative Exam Review
Q-mew-lah-t’v
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
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
Neutron
Electron
Positive
Nucleus
1.01
Neutral
Nucleus
1.01
Negative
Energy levels 0.00054
You can use the words to
help you remember which
goes with which!
Electrons are way smaller
than protons and neutrons
Reading the periodic table
1
Atomic number
What does the atomic number tell you?
The number of protons and electrons
H
1.01
3
4
Li
Be
9.01
6.94
11
12
Na
Mg
22.98
24.30
Symbol
The name of the element
Atomic mass
How heavy one atom of the element is
Why does helium have 2,
not 8 electrons in the
outside energy level?
Reading the periodic table
Column
1
2
3
What does the column number tell us?
The number of electrons in the
outside energy level
4
5
6
7
8
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
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 +8 - 10 = -2
8 protons (positives) with 10
electrons (negatives)
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)
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
1. -1 2. -3 3. +2 4. +1 5. Argon already has a full outside energy level, it is does form ions!
Answers:
Ionic bonds
What happens when one molecule that adds electrons to form an ion
meets a molecule that loses electrons to form an ion?
Mg
+2
O
-2
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:
0
Mg
+2
O
-2
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:
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
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
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!