Science 24 – Final Exam Review
Unit 1: Applications of Matter and Chemical Change
Synthetic materials are man-made. Provide examples
Alloy (pg. 10) – mixture of several types of metals that have properties of the original
metals that make up the alloy.
Polymers (pg. 9) – A large molecule made up of many small and identical submolecules.
Soap (pg. 7) – How does it work? Soap consists of a two-ended molecule. One end of
the molecule dissolves in grease and the other dissolves in water. This reactin enables us
to wash away grease.
HHPS (pg. 12) – hazardous household product symbols – make sure you know what the
HHPS and WHMIS symbols look like and what they stand for.
WHMIS symbols (pg. 19) – MSDS, WHMIS label, worker education.
Chemical reactions – substances that you begin with are referred to as the reactants.
After the chemical reaction, you are left with the products.
Indicators of chemical change:
-gases may be given off;
-new solids may be formed (precipitate);
-colour changes may occur
-release or absorption of energy
-odours given off
Combustion reaction – fuel burns in the presence of oxygen.
Complete combustion: fuel + oxygen  carbon dioxide + water + energy
Incomplete combustion: fuel + oxygen  carbon monoxide + carbon + carbon dioxide +
water vapour + energy.
Neutralization reaction – when an acid is added to a base to produce a compound and
water.
Exothermic reactions – energy is released into its surroundings.
Endothermic reactions – chemical changes that absorb energy. Eg. the initial
temperature of water mixed with ammonium chloride is 21oC, and the final temperature
of the mixture is 12oC.
Types of Chemical Reactions:
1. Simple Composition Reaction(pg. 44) - Two or more elements combine to form a
compound. Whenever you see two elements as reactants, you know that th reaction is a
simple composition reaction. The product is always a compound. Most simple
composition reactions are exothermic.
Element1 + Element2 ---> Compound
2. Simple Decomposition Reaction(pg. 45) - A reaction that breaks a compound into its
component elements is known as a simple decomposition reaction. Whenever you see a
compound as the only reactant, you know the reactioln is a simple decomposition
reaction. The products are always the elements. Most decompostion reactions are
endothermic
Compound ---> Element1 + Element2
3. Combustion Reactions (pg. 48)- A reaction in which a substance combines with
oxygen to produce heat the light. This occurs when things burn.
fuel + oxygen ---> carbon dioxide + water vapour + energy
4. Neutralization Reactions (pg. 48) - A reaction in which an acid reacts with a base to
produce a form of salt and water. This is the type of reaction that occurs if you take an
antacid.
acid + base ---> salt + water
Identifying common gases (pg. 26 – 27)
Carbon dioxide – Put a few drops of limewater in a test tube. Limewater turns cloudy in
the presence of carbon dioxide gas.
Insert a glowing wooden splint into the test tube. If the flame re-ignites, this indicates the
presence of oxygen gas.
Insert a burning wooden splint into the test tube. If the gas suddenly causes a squeal or
pop, this indicates the presence of hydrogen gas.
Law of Conservation of Mass: In a chemical reaction, matter is not created or
destroyed. If you start a reaction with 10 g of reactants, you will end up with 10 g of
products.
Balancing word equations:
3Li (s) + 2H2O(l) --> 2LiOH (l) + H2(g)- not balanced (There are 3 Li on the left and only
2 on the right. There are 4 H on the left and only 3 on the right).
How many atoms of each element are on the reactant side?
The coefficient 3 in front of Li (lithium) means there are 3 molecules of lithium. The
coefficient 2 in front of H2O means there are 2 molecules of H2O.
2H2O = 2H2 + 2O
The subscript 2 (2) beside hydrogen tells us that there are two hydrogen atoms in each H2
molecule.
H2 = H + H
So 2H2 = H + H + H + H = 4 hydrogen atoms
2O = O + O = 2 oxygen atoms
How many atoms of each element are on the product side?
The coefficient 2 in front of LiOH means there are 2 molecules of LiOH
2LiOH = 2Li + 2O + 2H
So there are 2 atoms of lithium, 2 atoms of oxygen, and 2 atoms of hydrogen.
In the next compound, the subscript 2 (2) beside hydrogen tells us there are two hydrogen
atoms in each H2 molecule.
H2 = H + H
Is this equation balanced?
reactant side = 3 lithium atoms, 4 hydrogen atoms, and 2 oxygen atoms
product side = 2 lithium atoms, 2 oxygen atoms, and 4 hydrogen atoms
No, the equation is not balanced because there are 3 lithium atoms on the reactant side,
and only 2 lithium atoms on the product side.
Chemical formulas: Eg. How many of each type of atom is in C6H12O6?
Ans. Carbon – 6 atoms
Hydrogen = 12 atoms
Oxygen = 6 atoms.
What happened in the Halifax Explosion in 1917?
The Greenhouse Effect (pg. 62)
Acids and Bases (pg. 67)
Liming – During liming, calcium carbonate is added to the waters of an acid lake. The
calcium carbonate neutralizes the acidic water, thus raising the pH of the lake water.
Sulphur Scrubbing (pg. 68) – Scrubbers remove the sulphur from the smokestack before
it reaches the atmosphere. *Make sure you read through figure 4.8 on page 68 and have
and understanding of the chemical reactions involved in scrubbing.
Corrosion (pg. 69) – any process that chemically breaks down or degrades metal.
Corrosion/rusting of iron: 4Fe(s) + 3O2(g)  2Fe2O3(s) Corrosion is an example of a
simple composition reaction.
Sacrificial Metal – (pg. 73)
Unit 2: Understanding Common Energy Conversion Systems
Energy is the ability to do work.
Forms of energy:
Potential energy is stored energy that can be converted to other forms. (pg. 82)
Kinetic energy is energy due to motion.
Thermal energy
Wind energy
Geothermal energy
Energy conversion systems (pg. 86) input energy  converter  output energy
Eg. electric kettle: input (electricity)  converter (heating element)  output (heat to
warm water)
Law of conservation of energy: input energy = useful output energy + waste output
energy
Thomas Carbide Wilson – invented one of Canada’s earliest electric generators.
Generating electric energy (pg. 102) – hydro-electric, thermo-electric (pg. 104),
thermonuclear. (pg 106).
Electric power involves the movement of electrons from the power source to the
customer.
• The speed of movement of electrons is called current and is measured in amperes.
• The electric force moving the electrons is called voltage and is measured in volts.
• The product of the current and the voltage is power. Power is measured in watts.
Work = force x distance
Example: A wagon is pushed with a force of 5 newtons a distance of 3 meters. How
much work is done?
Use the formula for work that you know and substitute in the values you are given.
work = F x d
work = 5 N x 3 m
work = 15 N.m or 15 joules
Power is the rate at which energy is transferred. The following formula can be used to
calculate power. Power is measured in Joules/second (J/s) or Watts (W).
power = energy/time
Please refer to pages 108 - 109 to see how the formula can be used to calculate power.
Example Question: An aquarium light bulb uses 7 J of electric energy in one second.
How many watts of power does this light bulb consume is 3 s?
Ans. What you know: power = ?; energy = 7J; time = 1s; power = energy/time
What you want to find out? - How much power is consumed?
Use the formula: power = energy/time = 7J/1s = 7 J/s
Express as watts: The light bulb uses 7W of power in 1s.
Amount used in 3s = 7 W/s x 3s = 21W
If the bulb uses 7J of electric energy in one second, then it must use three times as
much in 3 seconds.
power = 3s x 7J = 21W
Energy = power x time
Percent efficiency of an electric device = useful energy output/total electric energy
input x 100
(pg. 112) Example Question: An incandescent light bulb uses 30 000 J of electric energy.
It emits only 900 J of useful energy. What is the efficiency of the light bulb?
Ans. What you know:
useful energy output = 900 J
total electric energy input = 30 000 J
percent efficiency of device = useful energy output/total electric energy input x 100
What you want to find out? - What is the efficiency fo the incandescent light bulb?
Use the formula: percent efficiency of device = useful energy output/total electric
energy input x 100
=900J/30 000J x 100 = 3%
Photosynthesis (pg. 118):
Carbon dioxide + water + energy  glucose + oxygen
Respiration (pg. 119):
Glucose + oxygen  carbon dioxide + water + energy
Benedict’s solution – indicator used to test for the presence of glucose. When no
glucose is present, benedict’s solution is blue.
Energy conversion: plants to animals (pg. 122). Only about 10% of the energy in one
level is transferred to the next level. The other 90% is used for normal life functions such
as movement, growth, and reproduction.
Sources of Energy: carbohydrates, proteins, fats (pg. 125-127)
Metabolism (pg. 131)– the rate at which your body uses energy. Affected by age, time
of day, exercise, level of fitness.
Formation of Fossil Fuels (pg. 136). How are fossil fuels formed?
The coal used to generate most of Alberta’s electricity is sub-bituminous.
Extraction of fossil fuels (pg. 138)
Fractional distillation – process used to refine petroleum.
Combustion (pg. 48):
Fuel + oxygen gas  carbon dioxide gas + water
Incomplete Combustion (pg. 61) – occurs when there is not enough oxygen available.
The products produced by incomplete combustion include carbon monoxide, carbon,
carbon dioxide, water and energy.
Problems associated with use of fossil fuels: greenhouse gases, acid deposition
Unit 3: Disease Defence and Human Health
Microbes that cause disease are called pathogens.
Pathogens include:
Bacteria – need warm temperatures, moisture and food to thrive. Bacteria can be killed
by antibiotics.
Viruses – smaller than bacteria. Reproduce by taking over cells in the body.
Fungi - include molds, yeasts, and mushrooms. They cannot make their own food by
photosynthesis and therefore can only live if on a host organism.
Protists - celled organisms that share some characteristics with both animals and plants
(eg. amoeba, paramecium).
Communicable diseases - Communicable diseases are also called infectious or
contagious diseases. Communicable diseases can spread through air, water, food, or
direct contact.
Non-communicable diseases - These diseases are not caused by pathogens and therefore
cannot be passed from one organism to another.
Factors that increase your change of getting a disease: (pg. 166)
Food poisoning is caused by pathogens that enter the body through food or drink.
Food preservation methods: drying food, canning, salting, refrigeration, freezing,
vacuum packaging. Irradiation is a modern method of food preservation where food is
exposed to certain types of radiation energy.
Aseptic methods: practices used to stay clean and prevent the spread of disease (eg. use
sterile bandages, scrubbing exposed skin of surgeon before and after surgery).
Pandemic disease is a disease that affects a large proportion of the population over a
large geographic area (eg. AIDS).
Epidemic disease – a contagious disease that is not so widespread. This can be at school
or the work place.
Pandemic and Epidemic disease (pg. 178-179)
Physical defences against disease (pg. 194): nose and sinuses, tonsils and adenoids,
eyelids, tears, eyelashes, hair, ear, skin, stomach.
The inflammatory response (inflammation) results in swelling, redness, warmth, and
pain in the area of an infection. The increased blood flow attracts white blood cells to the
infected area. This response prevents antigens from spreading to nearby tissues, disposes
of cellular debris, and begins to repair any damage.
When a pathogen enters the body, white blood cells arrive to repel the invader.
Specialized white blood cells called macrophages surround and destroy damaged cells
and pathogens such as viruses and bacteria.
Please refer to figure 11.3 on page 195.
Antibodies (pg. 197)
Antigens – specific structures attached to pathogens that your body recognizes as
foreign.
Vaccine – an injection of weakened or dead disease pathogens.
Immune response (pg. 198)
Types of Immunity (pg. 199)
• Inherited Immunity — Humans have inherited immunity to most diseases of plants and
animals.
• Acquired Immunity — There are two types of acquired immunity — active and passive.
In active immunity, the body produces its own antibodies to defend against a specific
antigen. Active immunity takes several weeks before it can provide protection. In passive
immunity, the recipient is given antibodies, which were produced during an active
response in another animal, to defend against a specific antigen. Passive immunity lasts
for only a short time because the body destroys the borrowed antibodies. Passive
immunity provides immediate protection. In active and passive immunity, resistance may
be acquired by natural means or by artificial means such as vaccinations.
Alexander Fleming – discovered penicillin
What is DNA? – (pg. 212)
Chromosome - Human body cells contain 46 chromosomes arranged in 23 pairs that
hold all the genetic information. One chromosome of each pair comes from the mother
and the other chromosome of each pair comes from the father. Human sex cells contain
half the number of chromosomes. There are 23 chromosomes in a human egg cell or
sperm cell. Each human egg or sperm cell contains one sex-determining chromosome.
Females have two X chromosomes in their cells, while males have one X chromosome
and one Y chromosome.
Genotype is the term used to describe the genetic make-up of an individual.
Phenotype is the term used to describe the physical expression of the trait in an
organism. For example, the genotype of a tall pea plant could be described as Tt (one
dominant gene and one recessive gene). The phenotype of this particular plant would be
tall.
Geneticists tend to use capital and lower-case letters to name the factors for any trait. The
actual letter can change, depending on what is being recorded, but the use of capital and
lower-case letters is consistent. For any trait, an individual likely has one of the following
pairs:
• DD — two dominant factors.
• dd — two recessive factors.
• Dd — one dominant gene and one recessive gene for a trait. This is called a hybrid.
Inheritance of Factors— When gametes form during reproduction, the factors segregate
so that each gamete carries only one member of the gene pair. During fertilization, the
new organism inherits two factors— one from each parent.
Geneticists use a Punnett square (pg. 217) to predict the probability of offspring
inheriting certain traits.
A pedigree is a diagram that shows the history of a trait from generation to generation.
Pedigrees are designed to show all expressions of a trait, such as straight or curly hair, or
A, B, AB, or O blood type.
Inherited genetic disorders: (pg. 220)
Mutagen (pg. 220) – Environmental factors that can cause genetic mutations. (eg.
radiation, ultraviolet light, PCBs)
Unit 4: Motion, Change and Transportation Safety
Driving and BAC (Blood Alcohol Concentration) (pg 241) – legal BAC = 0.08 mg/mL
Example: A 50 kg female who has two drinks will have a BAC level of 0.09. How long
will it be until she will be able to drive?
Ans.
How far over the legal limit is the drinker?
0.09 BAC- 0.08 BAC= 0.01 BAC
How long will it take this drinker to get down to the legal limit?
0.01 BAC/0.015 BAC/h = 0.67 h (40.2minutes).
A 50 kg female with a BAC of 0.09 (0.01 over the legal limit) must wait a little more
than 0.67 hours (40.2 min) before it is legal for her to drive.
Velocity = distance/time
Stopping Distance:
While driving, drivers can change their velocity, which greatly affects stopping distance.
Stopping distance has the following two components:
• the driver’s reaction time — the distance a vehicle travels between the time the driver
sees a problem and then reacts to apply the brakes; and
• the vehicle’s braking distance — the distance the vehicle travels after the brakes have
been applied but before the vehicle stops.
Newton's first law is often referred to as the law of inertia. For moving objects, the law
states the following: An object in motion remains in motion, moving at the same
speed and direction unless acted upon by an outside force.
Newton’s Second Law: The change of motion of a body is directly proportional or
dependent to the outside force being applied on the object.
What is Momentum?
When mass and velocity are multiplied by each other, the product is a measure of the
object's motion. This quantity of motion is called momentum. Its effect becomes
extremely important during collisions. It can be calculated as follows:
Momentum = mass x velocity = mv And v=d/t
Calculating Momentum
Eg. A compact car with a mass of 750kg is travelling at 50km/h (15 m/s) What is the
momentum of the car?
Answer: Momentum = mass x velocity
= 750kg x 15 m/s
= 11250 kg.m/s
Eg. A grader working on a road construction project is hit by a sleepy dump truck driver.
The grader was travelling east at 25 km/h, and has a mass of 12 000 kg. The dump truck
was travelling west at 15 km/h, and has a mass of 30 000 kg.
a) What was the momentum of each vehicle before they collided?
Momentum = mass x velocity
Grader momentum = 12 000 kg x +25 km/h
= +300 000 kg.km/h
Dump truck momentum = 30 000 kg x -15 km/hr
= -450 000 kg.km/h
b) What is the total momentum after the collision?
Add the two momentums together.
(+300 000 kg.km/h) + (-450 000 kg.km/h)
= -150 000 kg.km/h
(Note: Because the momentum is negative, you know that after the collision, both
vehicles will be moving in the direction that the dump truck was moving in which is
west.)
A force is any push or pull on an object. Objects that are not moving will not move until
they are pushed or pulled with enough force. Objects that are moving will keep moving
until enough force is added in an opposite direction to stop them. Objects with a lot of
momentum will take more force and longer to stop.
Impulse is the ability to change the momentum of an object.
Impulse = force x time
Force = mass x (change in v)/change in time
Safety features (pg. 289)
Note: change in v = (v2 – v1)