Download Science and Technology 404

Science and Technology 404
Study guide – 2011
Date of Exam: Thursday, June 16th. Time: 9:00 am
Tutorial: Tuesday, June 14th. Time: 1:00 pm
Tips for writing your exam (you should read over these on the day of the exam):
 Look at the appendixes (the last few pages) right when you get your exam
so that you know the ‘tools’ that you have to work with
 ALWAYS include units in your answer when doing a calculation (otherwise
you will lose marks)
 Don’t leave any questions blank
 Use the amount of space given to you in the answer booklet as a guide for
how much you should be writing for each question
 If you don’t know the answer to a question, move onto the next one, and
come back to it once you’ve finished the exam.. you might find some hints
later on the exam that will help you
What you should do to study for the exam:
 Go through the study guide
 Look over your notes from throughout the year
 Do some questions from the worksheets (I will post these on the website as
well) that we have been doing throughout the year.. even if you have done
it before, it helps to try them again so that they are fresh in your mind. The
quicker you can do the questions, the more time you will have to do the
more challenging ones.
 Go over your old tests and quizzes, make sure that you know how to do the
questions (especially calculations)
Physical properties of solutions

Concentration (ppm) (textbook pp. 50-54 – workbook pp. 27-30)
The ratio for ppm is 1 mg of solute per 1 L of solution (or 1mg/L solution).

pH scale (textbook pp. 55-61 – workbook pp. 31-38)
PH refers to the level of acidity or alkalinity of a solution. A popular way of measuring this is by using a pH
indicator or scale.
A pH scale is a scale of values ranging from 1 to 14 that demonstrates how basic or acidic a substance is based on
an assigned number from the scale.
The lower the number the more acidic a substance will be – example Vinegar has a pH of 2 and is considered an
acid.
The higher the number the least acidic a substance will be – example bleach has a pH of 13 and is considered to be
a base (alkaline).
Chemical changes (textbook pp. 117-124 – workbook pp. 65-68)
Matter reacts in different ways to different things. We can change matter in 3 different ways:
Physical Change: During Physical change matter retains its original properties or characteristics. If we
look at water, it can become solid – in the case of a snowflake, hailstone or simply a piece of ice. It can
become a gas when heated to the point of boiling. In each situation when this matter is brought back to
a normal temperature it will return to its original state a liquid and the water molecules will not have
changed in any way. Only the state or the shape of water was altered.
Chemical Change: During Chemical change matter undergoes a transformation. Characteristics are
altered. At the atomic level chemical bonds are reorganized. The end result is a new substance. A
good example is the transformation of wood during the process of burning. Fire causes the wood
molecules to transform into charcoal and eventually cinder or ash. The original structure is completely
transformed. The wood can never return to its original state.
Nuclear Change or Transformation: This type of change relates to the transformation of the nucleus of
an atom. New elements are formed during nuclear fission or nuclear fusion. Fission is the process of
splitting the nucleus of an atom. Fusion refers to the combining of small atoms to produce larger
elements. An example of nuclear fission is the fission of uranium within a bomb. The atomic bomb is an
example. We now use this knowledge to produce electricity and radioactive isotopes for medical
purposes.
 Acid-base neutralization reaction (textbook pp. 119-120
By adding an acid to a base you can neutralize the base (or lower the concentration of base)
By adding a base to an acid you can neutralize the acid (or lower the concentration of acid)
The neutralization reaction of an acid with a base will always produce water and a salt as shown below:
HCl + NaOH → H2O + NaCl
 Law of conservation of mass (textbook p. 110 – workbook pp. 55-60)
The total mass of the reactants ends up being equal to the total mass of the products. If you mix 207
grams of BaCl2 with 138 grams of K2CO3, you will get 148 grams of KCl. How much BaCO3 will you get?
BaCl2 + K2CO3 → BaCO3 + 2 KCl
Organization of matter (textbook pp. 6-29)
 Rutherford-Bohr atomic model (textbook pp. 13-15, 27-28 - workbook pp. 3-6, 14)
Know the atomic number of the element so that you can determine the number of protons and
evidently the number of electrons.
What period the element belongs to because the period tells us the number of electron shells.
What group is it found in within the periodic table so that we can determine the number of valence
electrons in the outermost shell.
To draw Bohr-Rutherford Diagrams:
1. Draw the nucleus as a solid circle.
2. Put the number of protons (atomic number) in the nucleus with the number of
neutrons (atomic mass – atomic number) under it.
3. Place the number of electrons (same as protons) in orbits around the nucleus by
drawing circles around the nucleus.
Remember, 1st shell – 2 electrons, 2nd shell – 8 electrons, 3rd shell – 8 electrons,
4th shell – 18 electrons.
 Lewis notation (textbook p. 27 - workbook pp. 13-14)
represents valence valence electrons
also named electron dot notation because dots representing valence electrons are placed around the
chemical symbol of the element

Groups and periods of the periodic table (textbook pp. 17-22 - workbook pp. 7-12 )
The Periodic table is a chart which lists specific details about all of the different elements found on our
planet. It includes the names of each element and specific details about their atomic structure. It has
become an invaluable tool to studying chemistry.
The elements
o Each square represents an element
o Within the square the chemical symbol in the middle represents the element
o Below the symbol is the name of the element
o The atomic number is found at the top of the square and the relative atomic mass is found at
the bottom
The arrangement of the elements in the periodic table
o The elements are arranged in order of increasing atomic number
o Each row is called a period and are numbered from 1 to 7
o Each column is called a group and is numbered with a combination of numbers from 1 to 18 and
letters A and B
o Elements are classified into three categories (metals, non-metals and metalloids). The staircase
structure found in the right hand side of the periodic table helps to locate these categories
Ecology
 Study of populations (textbook pp. 292-309 - workbook pp. 153-162)
Population : total of individuals of a same species that live in a same area
Population density: number of individuals per unit of area or unit of volume of a given territory
Biological cycle: the range of steps that an organism goes through over the course of its life
Polulation size is affected by a variety of factors including:
 Birthrate: the number of individuals born within the species
 Deathrate: the number of individuals that die within the species
 Immigration: the number of individuals from neighbouring regions that join the population
 Emigration: the number of individuals that leave the population
There are 3 main ways to calculate population size:
1. Counting individuals
Count each individual in a given area
2. Counting by sample area
Count the individuals in a section and extrapolate with the following formula:
3. Mark and recapture
Capture and tag some individuals, then release them and do a second capture. The
following formula will allow an estimation of the population size:
Population density is the number of individuals per unit of area or unit of volume of a given territory
and is calculated as follows:
Population Distribution: 3 types
1. uniform- evenly spaced, usually due to competition for resources.
2. clumped- where certain habitats have better living conditions.
3. random
Ecological Factors- Aboitic (Non-living) vs. Biotic (living) – See chart on page 300 in textbook
 Dynamics of ecosystems (textbook pp. 318-329 - workbook pp. 163-174)
The trophic structure of an ecosystem forms an ecological pyramid. The base of this pyramid represents
the producer trophic level. At the apex, or top, is the highest level consumer or top predator. The
pyramid of biomass is calculated by multiplying the average weight for organisms times the number of
organisms at each trophic level. Only 10% of the energy in one trophic level passes up to the next
trophic level.
The biological cycle of a population is composed of alternating periods of rise and fall in its size. These
periods are of fixed duration and are repeated continually.
If the population of a prey species goes up, it will be followed by an increase in the population of a
predator species. After a certain amount of time, the increase in predator population will have a
negative effect on the prey population, causing it to decline. As the prey population declines, there will
be less for the predator to eat, causing the population to decline as well. The graph below displays this
cycle.
The types of interaction between individuals in a community are:
 Competition
 Predation
 Mutualism
 Commensualism
An ecosystem is a community of living organisms interacting with one another and with the nonliving
components of the environment they inhabit.
Communities are rated on their BIODIVERSITY, based on two factors (you need to define them). You may
be asked to calculate these.
1. Species Richness:
2. Relative Abundance:
Communities are formed in different BIOMES. See the handout on biomes for more information.
The flow of energy is in the direction of the arrows. Therefore the species that the arrow is pointed
towards is the one that eats the species that the arrow comes from.
Mechanical Engineering
Mechanical engineering is a branch of engineering that focuses on the design, production, analysis,
working and improvement of technical objects with moving parts.
Characteristics of linking of mechanical parts (textbook pp. 427-428)
Most machines are made of multiple parts and the way that these parts function is greatly determined
by the way that they are joined together.
Links can be :
Direct – 2 parts hold together without a linking
Indirect – requires a component to hold the parts
component
together (ex: a nail)
Rigid – the surfaces of the linked parts do not
Flexible – the surfaces of the linked parts can
move
move (ex: a spring)
Removable – the linked parts can be separated
Non-removable – separating the linked parts
without damaging either their surfaces or the
damages their surfaces or the linked parts (ex:
linking component (ex: screws and bolts)
glue)
Complete – prevents the linked parts from moving Partial – at least one part can move independently
independently
of the other parts
Consider the link below between the doorknob and the door.
Identify the characteristics of this link by checking the correct boxes.
direct

indirect

rigid



flexible



removable
complete
non-removable
partial
Guiding controls (textbook pp. 431-432)
A guiding control restricts the movement of a moving part of a machine.
An example of this would be the grooves of a window frame that allow the window to move up and
down but keep it from falling out. This is known as translational guiding.
Another example would be the axle of a wheel allows the wheel to turn while restricting all other
movement. This is known as rotational guiding.
Speed changes (textbook pp. 442-443)
A speed change occurs in a motion transmission system when the driver does not turn at the same
speed as the driven component or components.
Speed changes in multiple-gear motion transmission systems
Speed change
Increase
Decrease
No change
Friction gear systems
Belt and pulley systems
Motion is transmitted from one gear or pulley to a gear
or pulley of smaller diameter
Motion is transmitted from one gear or pulley to a gear
or pulley of larger diameter
Motion is transmitted between two gears or pulleys of
the same diameter
Gear trains
Chain and sprocket systems
Motion is transmitted from one rear or sprocket to another
with fewer teeth
Motion is transmitted from one gear or sprocket to another
with more teeth
Motion is transmitted between two gears or sprockets with
the same number of teeth
Of the systems below, system 2 would have the greatest speed change because the difference between
the diameters of the gears is the greatest.
Motion Transformation (pg. 435-449 in textbook)
You don’t need to memorize these, but you should be able to recognize a particular type of motion
transmission or transformation, and from the diagram figure out how they work. You should also know
the difference between transformation and transmission.
The Earth and Space
Biogeochemical Cycles
The Nitrogen Cycle:
Source: www.physicalgeography.net/fundamentals/9s.html
** Practice questions: WB pg. 135-140
1. What is the purpose of the nitrogen cycle? What is nitrogen used for by living things?
2. What kind of organisms use atmospheric nitrogen (N2) in their life processes?
3. What are main sources of atmospheric nitrogen?
4. What is eutrophication?
The Carbon Cycle:
Source: http://www.youcontrol-climatechange.co.uk/climate/carboncycle.html
1. What is the chemical equation for photosynthesis? How does this compare to that of
respiration?
2. How does the carbon cycle relate to global warming? Explain how/where it affects the diagram
below.
Source: http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/C/CarbonCycle.html
Energy Resources
Lithosphere
Hydrosphere
Different Energy Sources and their Environmental Impacts
Energy Source
Hydroelectricity
Method of Production
kinetic energy of water 
mechanical energy (turbine)
 electric energy (generator)
Environmental Impact
flooding of huge areas of
land; upsetting of
ecosystem; disruption of
native cultures
Tidal Electricity
kinetic energy of water 
mechanical energy (turbine)
 electric energy (generator)
Unattractive; difficult for
some marine activities;
can harm aquatic animals
Energy Source
Thermonuclear Plants
Method of Production
Atomic energy  thermal
energy (steam) 
mechanical energy (turbine)
 electrical energy
(generator)
Environmental Impact
Danger of nuclear accident
such as the Chernobyl
disaster; disposal of
radioactive wastes
Thermal Plants
Chemical energy from
burning coal  thermal
energy (steam)  electrical
energy (generator)
Acid rain caused by
emissions of SO2 and NO2.
Thermal energy 
mechanical electrical energy
(turbine)  electrical energy
(generator)
Can emit hydrogen
sulphide and carbon
dioxide – chemicals that
contribute to acid rain.
Energy Source
Wind Power
Method of Production
Wind’s kinetic energy 
mechanical energy (turbine)
 electrical energy
(generator)
Environmental Impact
Take up large expanses of
land; can be harmful to
birds etc.
Energy Source
Method of Production
Environmental Impact
Solar Plants
[Solar Cells]
Radiant (light energy) 
thermal energy  kinetic
energy (steam) electrical
energy (generator)
[Solar Panels]
Radiant (light energy) 
thermal energy
Take up large expanses of
land.
Solar
Atmosphere
Geothermal Plants
** Practice Questions: WB pg. 103-107
1. What are the advantages and disadvantages of each of the main energy resources?
Hydrosphere: Salinity
**Practice: WB pg. 105
1. What does the word salinity mean?
2. What percentage of the Earth’s water supply is fresh water?
3. What percentage of the Earth’s water supply is salt water?
4. Why does saltier water sink, while less salty water floats?
5. How does dissolved salt play a role in the ocean’s circulation?
Atmosphere: Air Masses
Air mass: is a large
expanse of the
atmosphere that
has a relatively
uniform
temperature and
humidity.
Fronts: when two
air masses meet,
they can form a
cold front or a
warm front.
Warm fronts: When warm air meets cold air
Cold fronts: When cold air meets warm air.
** Practice: WB pg. 119-122
Space: The Earth-Moon System
Did you know? That many scientists believe that the moon is a fragment of the Earth that was broken off
during a meteorite collision 4.6 billion years ago!
Tides: the rise and fall of water in the seas and oceans caused by the gravitational force of the moon
(primarily) and to a lesser extent, the sun (secondary).
When the sun and the moon are aligned, the
high tides are highest and the low tide are
lowest.
These are called SPRING tides.
When the sun and the moon are perpendicular,
the high tides are at their lowest, and the low
tides are at their highest.
These are called NEAP tides.
Due to the Earth’s rotation, there are two high
tides and two low tides experienced on Earth
every day.
**Practice: WB pg. 129-130
1. Why are there two high tides and two low tides each day?
2. Why do two high tides happen on Earth at the same time, one on the side facing the moon, and
one on the opposite side?
3. How can tides be used to generate electricity?
Electricity and Electromagnetism
-
-
Electrical Charges:
remember from our atomic studies that:
o Protons carry a positive charge (and are found in the nucleus)
o Neutrons carry no net charge (and are also found in the nucleus)
o Electrons carry a negative charge (and surround the nucleus in orbitals)
ions are electrically charged atoms, and:
o
o
o
o
A positively charged body has more protons than electrons (p+
> e-)
A negatively charged body has more electrons than protons (p+ < e-)
Like charges repel whereas opposite charges attract.
There are electrical forces between objects that are charged which cause them to interact
the way they do (attraction or repulsion). These electrical charges can neither be created
nor destroyed, they can simply be passed from one material to another.
**Practice: WB pg. 77-78
We are given four spheres, A, B C and D. Sphere A is positively charged and the charges on spheres B, C
and D are unknown.
The following diagram shows what happens to these spheres if we suspend them two by two close to
each other.
A
B
B
C
C
Given the diagram above, what are the charges on spheres C and D?
A)
Sphere C is positively charged and sphere D is negatively charged.
B)
Sphere C is positively charged and sphere D is positively charged.
C)
Sphere C is negatively charged and sphere D is negatively charged.
D)
Sphere C is negatively charged and sphere D is positively charged.
D
Ohm’s Law
is a relationship between the current intensity, the voltage and the
resistance in an electric circuit.
V
I
R
V – voltage or potential difference, measured in VOLTS (V)
I – current intensity, measured in AMPERES (A)
R – resistance, measured in Ohms ()
Electric Circuit: is the path along which an electric current will flow continuously in a loop.
There are two kinds of circuits: series and parallel.
Series Circuit, has no branches.
Parallel Circuit, has branches!
**Practice: WB pg. 79-80, 84 # 1-2
Ohm's Law gives the voltage at the terminals of a resistance as a function of the current intensity in the
resistance.
Which one of the following graphs represents Ohm's Law for a given resistance?
A)
C)
Voltage
0
Current
Voltage
0
Current
B)
D)
Voltage
0
Current
Voltage
0
Current
Energy and Power
The power of a particular appliance or circuit can be calculated using the following equation: P=VI.
Where P is the power in Watts, V is the voltage, and I is the current intensity.
With the power, the energy can also be calculated, this time with the equation: E=Pt. Here E is energy,
P is power, and t is time. The energy can be expressed in either Joules (J) or Kilowatt hours (kWh),
depending on which units you use for power and time:
If power is in kilowatts, and time is in hours, then energy is in kWh.
If power is in watts, and time is in seconds, then energy is in Joules.
Energy Efficiency
We can also calculate the energy efficiency of an appliance, using the following equation:
Energy efficiency = Amount of useable energy
X 100
Amount of energy consumed
The energy consumed is the total energy going into the appliance, whereas the useable energy is the
amount of energy that actually goes into performing the function of the appliance. The rest of the
energy is lost, usually as heat.
Electrical Engineering
 Power Supplies: Complete the following table (TB pg. 463):
Power Supply
Battery
Advantages
Disadvantages
Electrical Outlet
Photovoltaic Cell
 Insulators and Conductors:
-
-
some substances are very adept at allowing the passage of electrical charges, whereas some
materials impede the flow of electrons.
Conductors are substances that permit the free flow of electrical charges. Electrolytic solutions
are good examples of conductors, so are metals.
Insulators are substances that impede (prevent) the flow of electrical charges. Pure water, air,
Styrofoam, and most non-metals are good examples of insulators.
Conductors and insulators are opposites:
o If you are a good conductor, you’re a poor insulator.
o If you are a good insulator, you’re a poor conductor.
Semi-conductors are substances that are variable conductors: sometimes under some
circumstances they are good, and under other circumstances they are lousy. Semi-conductors
are often metalloids, and are used in various electrical circuits.
 Protection:
If a short circuit (wire with no resistors attached that offers a path of least resistance) or an overload
(too many appliances attached to the same circuit) occurs, there is a risk of fire or electric shock. To
prevent these problems, a protective device is installed.
The role of protection is to automatically stop current flow in the case of a power surge.
There are two main types of protection, complete the chart below (TB pg. 467).
Protection
Description
Fuse
GOOD
BAD
Breaker
 Control:
Sometimes it is useful to be able to control a circuit by turning it off or on without removing the power
supply. In such a case a switch is used. A switch is a device that can open or close a circuit.
When a switch is OPEN, the electric current
will not flow through the circuit, and the
devices connected will not function. When a
switch is CLOSED, the electric current will
flow through the circuit, and the devices
connect will function as intended.
**Practice: WB pg. 237, 239, 241 (note: #5 is continued on pg. 242).
 Energy Transformations:
Remember that electrical Energy (VIt) can be converted into any other form of energy. The law of
conservation of energy states that energy can neither be created nor destroyed, it is simply transferred
or transformed.
**Practice: WB pg. 244