Science 30 Diploma Prep Unit A

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Science 30 Diploma Prep – General Diploma Info

For All You Need to Know about Science 30 (Well most of it anyway…)

Your school-awarded mark is worth 50% of your final mark in Science 30. Your Science 30

Diploma Examination mark is worth the other 50% of your final mark.

The Science 30 Diploma Examination consists of 39 multiple-choice questions and

16 numerical-response questions worth one mark each (may shift slightly). There is no penalty for guessing—never leave a blank on your answer sheet. Numerical-response questions are worth one mark each and require you to fill in the correct sequence of numbers on your answer sheet.

The best way to prepare to write the Science 30 Diploma Examination is to start with a positive attitude and establish good study habits. The skills and knowledge that you gain in the course are essential to your success on the diploma examination.

Your exam is on Monday, January 30 th from 9:00am-11:30am (You should arrive at least 15 minutes prior to your exam as we will take you into the gym early to setup)

Breakdown of Exam

Outcome Unit and Topic

A1/A2 Circulatory and immune systems

Focus

10–15%

Approx

Number of

Q’s

7

A3 Genetics

B1/B2/B3 Chemistry (Environmental, Acids and

C1

C2

D1/D2

Organic Chem)

Field theory and electrical energy

Electromagnetic system and Astronomy

Energy and the environment

General Manipulated/Responding/Controlled

Variables or PESTE Question

10–15%

20–30%

13–18%

7–12%

20–30%

2%

7

13

9

5

13

1

Getting Ready to Write the Exam

Schedule review periods well in advance. Keep your reviews short and frequent. Create review tools, such as summaries of class notes for each unit and flashcards of scientific diagrams and processes. Prepare a checklist of everything you need to know for the exam

(included). Include major unit topics, chapter quizzes, labs, and assignments. Check-off concepts from the Diploma Prep material once you have mastered it.

Suggested 9-day Study Schedule for Science 30

Day 1

Circulatory

System (Unit A

– A1 and A2)

Day 2

Genetics (Unit

A – A3)

Day 3

Acids and

Bases (Unit B –

Day 6

EMR

(Unit C – C2)

Day 7

Environment

(Unit D –

D1/D2)

B1)

Day 8

Review

Day 4

Organic

Chemistry

(Unit B – B2 and B3)

Day 9

Review

Day 5

Field Theory and Circuits

(Unit C – C1)

Exam Day

Exam-Day

On exam day, arrive early and get organized. You are responsible for providing your own

HB pencil, eraser, and calculator for writing the diploma exam. Double-check your batteries!

No print or electronic dictionaries or texts are allowed. Remember to relax and do your best.

Mark questions that you can’t answer immediately and come back to them later. Pace yourself and answer every question.

Read the instructions, and then read the context and the question or questions you will be answering. Carefully read all the information given in the context provided. For multiplechoice questions, read the stem of the question and formulate an answer to the question in your mind before looking at the four alternatives given. Then look at the four alternatives and find the answer among them. Some questions are more difficult than others and will require you to choose the best answer. For numerical-response questions, pay close attention to the instructions below the question so that your answers are expressed or rounded appropriately with the correct number of digits.

Numeric Response

The numeric response will follow the same format as during our exams.

Note there will be only four boxes. There are no negative values and there may be more than one correct answer for numeric response questions.

Use all the digits during your calculations and make sure you round correctly at the end.

Pay attention to how many digits it says to record.

Example

The hydronium ion concentration, [H3O+(aq)], for a solution with a pH of 5.500, expressed in scientific notation, is a.bc × 10 –d mol/L.

The values of a, b, c, and d are ______, ______,

______, and ______.

(Record all four digits of your answer in the numerical-response section on the answer sheet.)

General Science 30

One of the major goals of Science 30 is to produce scientific-literate members of society.

Being safe, inquisitive, respectful and competent are all STS-goals associated with these goals. Many of these goals are difficult to test in a multiple choice test, so we will focus on the few that may come up.

Scientific Method

To be termed scientific, a method of inquiry must be based on gathering observable empirical and measurable evidence subject to specific principles of reasoning.

A scientific method consists of the collection of data through observation and experimentation, and the formulation and testing of hypotheses.

Manipulated variable

The variable that is deliberately changed by the scientist.

“What is the scientist changing in this

experiment?”

Responding variable

The variable that changes as a result of the change in the manipulated variable.

Controlled variables

All the variables that are kept the same so that any change in the responding variable can be attributed to the change in the manipulated variable.

What is the scientist looking for or trying to

measure?

What does the scientist have to do in order for this to be a

fair test?

General Safety – WHMIS Symbols and MSDS Safety Sheets

WHMIS is a symbol of symbols used in schools and workplaces to identify and classify potentially dangerous materials. Each substance is shipped with an MSDS that states the information about the material including hazards, safety precautions, disposal, etc.

Warming

Compressed

Gas

Flammable and

Combustible

Oxidizing

Material

Poison (Short

Term)

Toxic (Long

Term)

Biohazardous

Corrosive

Dangerously

Reactive

Symbol Risks

•Could explode due to pressure

•Could explode if heated or dropped

Examples

Acetylene, hydrogen gas and oxygen gas.

Methane, acetone

May ignite spontaneously

May be a material which will release flammable products

Increase fire and explosion hazard

May cause combustibles to explode or react violently

Ozone, chlorine, and nitrogen dioxide

May be fatal if ingested or inhaled

May be absorbed through the skin

Small volumes have a toxic effect

Cyanide, mercury, drano,

anti-freeze

May cause death or permanent injury

May cause birth defects or sterility

May cause cancer

Infectious agents or biological hazard.

Asbestos causes cancer, ammonia is an

irritant.

Viruses,

Yeasts,

Moulds,

Bacteria and Parasites

Acids, ammonia.

Eye and skin irritation on exposure

Severe burns/tissue damage on longer exposure

Lung damage if inhaled

May be chemically unstable

May explode if exposed to shock or heat

May release toxic or flammable vapour

Ozone, radioactive material

Science 30 Diploma Prep Unit A – Circulatory and Genetics

The two major outcomes for this unit are:

 analyze the function of the circulatory and immune systems in maintaining human health (Unit A, GO A1 and A2) 10–15%

 apply the principles of heredity and molecular genetics to human diseases and technological applications (Unit A, GO A3) 10–15%

General Outcome 1

Students will analyze how the human circulatory system facilitates interaction between blood cells and the external environment and investigate cardiovascular health.

The heart and blood flow - Know the four chambers

of the heart, the septum, where the valves are located, and how the valves work (specific names of valves are not needed). Know how blood circulates through the body, the differences in structure and function between arteries and veins, and that gas exchange happens at the cellular level in capillaries.

Remember arteries are oxygen rich and veins are oxygen poor. In addition, remember the two exceptions to the rule: the pulmonary artery and

pulmonary vein.

Be able to trace the pathway of the blood from the vena cava, through the heart, to the lungs, back to the heart, and out of the aorta.

Understand the chambers work at the same time with one another. Know that a natural pacemaker is responsible for the rhythmic contractions of the heart chambers. The heart receives oxygen through the

coronary arteries. The systolic pressure is when the ventricles contract and diastolic is when the ventricles relax (i.e. 120/80 blood pressure – measured in the arteries).

Know the structure and function of the main components of blood- red blood cells, white

blood cells, platelets, and plasma. Be able to recognize the relationship between iron, hemoglobin, and oxygen transport.

Health of one’s heart can depend on a number of factors including exercise, lifestyle, diet, gender, and family history. Understand higher blood pressure, sustained high heart rate, and high cholesterol levels have a negative impact on your heart. Understand in general a number of blood/heart diseases and the immediate and long-term impacts (i.e. heart attack,

arthrosclerosis, and stroke).

General Outcome 2

Students will analyze the defense mechanisms used by the human body to protect itself from pathogens found in the external environment.

Pathogens in the environment enter the circulatory system by getting by your body’s first

line of defence (things like tear, skin, mucous, and stomach acid). These pathogens may be in the form bacteria, viruses, or mosquito-borne parasites. Washing your hands and improving sanitation in areas reduces the amount of harmful pathogens entering your body.

The Immune Response – a pathogen will break the first line of defence and is consumed by a

macrophage (white blood cell). Pathogens contain markers called antigens that are now displayed by the macrophage. Helper T-Cells recognize the antigen as foreign material and signal for help. They signal to the B-Cells, who help produce antibodies that attach to the antigens and make it easier to identify foreign pathogens. They also signal to killer T-cells who destroy the foreign pathogens. Memory cells (both B and T) remember the antigen so that it can be easily tracked and killed if it returns. Suppressor T-cells signal an end to the immune response.

Vaccines act by using a partially dead or completely dead pathogen and injecting it into the blood stream. The immune response is then carried out in order for the body to remember the disease. Vaccination programs are beneficial in controlling epidemics or dealing with concerns about the spread of possible infection, such as tetanus, smallpox and the latest cases of H1N1. Scientific studies have shown there are very small possibilities for reactions from vaccination, yet people will often listen to anecdotal stories over scientific studies. (For instance, study after study has found no link between autism and vaccinations, yet the rumour continues).

Problems with the immune system can result in people getting sicker more often.

Antibiotics are often used to kill bacteria, however if they are not used correctly they can create resistant strains in the environment. An autoimmune disease is when the body starts attacking its own cells mistaking them for foreign pathogens ( For example, multiple sclerosis is when the immune system attacks the nerve cells in the spinal cord and brain).

General Outcome 3

Students will apply the principles of heredity and molecular genetics to explain how human diseases can arise from inherited traits, the risks and benefits of genetic technology, and the need for ethical considerations in the application of scientific knowledge.

The general characteristics of the structure and function of DNA should be understood.

Students are expected to know the base names and how the bases pair. They should be able to describe chromosomes, alleles, and DNA. A general description of the main events of

DNA replication (such as the molecule unzipping down the middle and new specific bases linking) and protein synthesis using the amino acid table in the data booklet is required.

Use the data book to correctly know the names of the nitrogen bases.

A general description of the sequence of events for mitosis and meiosis is needed. For example, students should know that chromosomes double, line up at the equator, and separate and pull to opposite poles. Students will need to know the terms haploid (n) and

diploid (2n), homozygous and heterozygous in their descriptions. Students should be able to make the connection between fertilization and crosses in Punnett squares. Know the difference between phenotypes – what is expressed (i.e. blonde hair and blue eyes) and

genotypes – what the gene looks like (i.e. BB or Tt). Be able to read a pedigree chart and infer phenotypes and genotypes.

To understand the role of DNA, students need to know that proteins make up the structure of the cell and regulate the chemical reactions in the cell. Know the terms enzyme and

hormone. Diploma examinations will place more emphasis on the risks and benefits of genetic technologies and their ethical considerations from a variety of perspectives than in previous years.

Genetic engineering is the manipulation of genes and the DNA code. Genetic therapy involves isolation of a gene involves identifying and extracting a certain gene. Next a gene spliced into a cell (like bacteria) to grow and multiply and transform the target DNA. The new DNA then replicates and multiplies.

Key Advantages of genetic engineering: producing new medications (ex. Insulin or vaccines), genetically modified foods resistant to insects, pests, or bacteria with a decreased focus on fertilizers and pesticides. Larger yields (production), stay fresh longer, or more nutrients. Future possibilities of elimination genetic diseases in human beings (ex.

Cystic fibrosis)

Key Disadvantages of genetic engineering: Can introduce unwanted resistant strains of plants or organisms into an environment. Allergies with genetically modified foods. Ethical issues of playing with the DNA “playing God”. Ethical issues of using animals for testing purposes. Using stem cells, female eggs for testing. Unintended consequences on ecosystems not foreseen when a new organism is introduced.

Science 30 Diploma Prep Unit B – Chemistry

The two major outcomes for this unit are (20-30%):

 analyze the sources of acids and bases and their effects on the environment

 analyze the sources of organic compounds and their effects on the environment

 analyze, from a variety of perspectives, the risks and benefits of using chemical processes in meeting human needs and assess technologies for reducing the impact of chemical compounds on the environment.

General Outcome 1

Students will analyze the sources of acids and bases and their effects on the environment.

Before analyzing chemical reactions, you will need to be able to balance chemical equations.

Based on the chemical formula, you should be able to identify acid, basic, or neutral based substances.

Acids and Bases common acids can be found in your data booklet on p.12

 most acids produce H+ ions in aqueous solutions (Ex. Hydrochloric, nitric, acetic acid)

 most bases produce OH- ions in aqueous solutions (Ex. NaOH, ammonia, calcium hydroxide)

 Better definition o o acids are proton donors (lose a H+ ion) bases are proton acceptors (accept a H+ ion)

Properties of Acids taste sour, electrolytes, react with bases to form salts and water, corrsoive, evolve hydrogen gas (H

2

) upon reaction with an active metal and turn litmus paper RED.

Properties of Bases taste bitter, feel slippery or soapy, turn litmus back to BLUE, electrolytes, some are also corrosive, react with acids to form salts and water

The pH Scale

The pH scale measures how acidic or basic a substance is. The pH scale commonly ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic.

The pH scale is logarithmic and as a result, each whole pH value below 7 is ten times more acidic than the next higher value. For example, pH 4 is ten times more acidic than pH 5 and

100 times (10 times 10) more acidic than pH 6.

Concentration of [H+] ions is found to be a logarthimic scale (multiply concentration by 10 for every 1 pH change)

When writing acid-base reactions: identify the acid and the base using the table on p. 12 of your data table. Stronger acids are higher up in the acid column, stronger bases are lower

down in the base column. Identify the conjugate forms of each by moving across the table.

To identify the acids and base pairs, look for which substance gained the H+ ion (the original base) and which substance lost the H+ ion (the original acid)

When acids are put into water, they dissociate into ions. The H+ ion will bond to polar water and form H

3

O + ions called hydronium.

Indicators are often used to identify substances as acids or bases.

Colour changes let you know when the pH changes.

For example, if bromocresol green will turn yellow for pH lower than 3.8, will turn blue for a pH greater than 5.4 and it will be a mixture-green for pH between 3.8-5.4.

We will often use more than one indicator in order to get the smallest possible pH range and identify the pH value.

A common application of indicators is to perform a titration which is used to find either a concentration or amount of acid/base. Know the steps in procedure and how to read a

burrette.

In a titration, you add a specific volume of acid or base in order to neutralize another substance. You can then calculate the concentration of substance you used, based on the

molarity of the acid or base.

Acid Deposition

The main acid-forming pollutants are sulphur dioxide (SO

2

) and oxides of nitrogen (NOx).

These substances interact with water in the atmosphere to form acids that return to the earth in wet (rain or snow) or dry (being absorbed in the atmosphere) deposits.

• SO

2

+ H

2

O ==> H

2

SO

3

(sulphurous acid)

• NO

2

+ H

2

O  HNO

3

(nitric acid)

Sulphur dioxide comes from smelters, gas processing plants, oil sands plants, coal-fired power plants, and transportation (trains and vehicles). Oxides of nitrogen come from the same sources with nearly half of it coming from transportation sources (cars, trucks, airplanes, etc.).

Acid deposition has different effects in different areas of Canada.

• Many parts of Eastern Canada and

Western B.C. have naturally acidic soils. Acidic soils cannot neutralize acid; therefore acids build up faster in these soils.

• Other areas including parts of British Columbia, central and Alberta have large amounts of limestone in the rock beds and lakes. These lakes “buffer” the acid…

• Minerals like calcium, magnesium, potassium and sodium are leached from the soil and carried away. (leaching – loss of nutrients through dissolving with the liquid in soil) Toxic metals like aluminum, manganese, mercury, cadmium and lead become more soluble by the chemical action of the acids. This allows the toxic metals to be absorbed by the plant roots and can cause serious damage or death to the plant or microorganisms.

• Toxic metals like aluminum, mercury, lead, and cadmium are washed into the lakes from the soil. Collect in fish and other aquatic animals making them unsuitable or dangerous for people to eat (biomagnifcation).

• Acid rain even affects historical monuments, such as the Parthenon in Greece,

Westminster Abbey in England and the Taj Mahal in India by turning the marble into a crumbly rock called gypsum. Modern day works like steel bridges, vehicles and other metallic structures corrode or rust at a much faster rate because of acid rain.

Buffering Capacity - Ability to be exposed to an acid or base and not change pH

• Soil/Limestone in lakes  carbonate ion

• Blood  hydrogen carbonate and carbonic acid

Once too much of an acid/base is added, the buffering capacity is exceeded and the pH changes

The pH changes slowly in a titration due to buffering.

Once the capacity is reached, a sharp change occurs.

General Outcome 2

Students will analyze the sources of organic compounds and their effects on the environment.

You will need to be able to name and identify organic compounds including: the hydrocarbons (alkanes, alkenes, alkynes, benzene ring) and functional groups

(halogenated hydrocarbons, alcohols, carboxylic acid, and esters). Use the data book to help you identify. Naming convention is required up to three carbon long chains.

Remember that esters form from the combination of carboxylic acids and alcohols and

have a sweet smell to them. Hydrocarbons are often used in industry and the home as pesticides, solvents, and propellants. For example, some uses are chlorofluorocarbons

(CFCs) as refrigerants, the manufacture of plastic foam products; ethanol as a solvent and as a gasoline additive; ethanoic acid as vinegar; ethyl ethanoate as nail-polish remover.

Understand benzene rings area a known carcinogen (cancer-causing) and pollutant in the environment since the rings are difficult to break down. Crude oil petroleum contains numerous benzene rings, so you probably shouldn’t be touching or inhaling. Halogenated hydrocarbons are often used in industry as solvents, pesticides, or refrigerants for cooling, but have been found to have a number of hazards to the environment (i..e DDT, CFC)

General Outcome 3

Students will analyze, from a variety of perspectives, the risks and benefits of using chemical processes in meeting human needs and assess technologies for reducing the impact of chemical compounds on the environment.

For example, over-fertilization of farmland leads to increased algal growth and the death of aquatic life. Ground-level ozone and particulates should be recognized as components of

photochemical smog (brownish-red haze produced by reaction of sunlight and automobile exhaust in a reaction of nitrogen oxides).

The introduction of environmental contaminants, i.e., herbicides, pesticides, DDT, CFCs,

SO2(g), CO2(g), affects living systems globally as the chemicals can bioaccumulate over time.

Know the terms:

Lethal dose (LD, LD 50) – the concentration that would theoretically kill 50% of a population in a certain area.

Polychlorinated biphenyls or PCBs –originally used as coolants, very similar to

CFC’s. Large amounts of benzene rings and chlorine atoms made it difficult to break down and caused problems to the immune system, brain development, sex organs, and effects in pregnancy.

Particularly persistent organic pollutants (POPs) - are organic compounds that are resistant to environmental degradation – most are pesticides and almost all are created by humans. Large amounts of POP’s contribute to health hazards such as cancer.

Biochemical oxygen demand or BOD – deterring the amount of dissolved oxygen needed by aquatic life by measuring the amount of organic compounds in the water.

Used as an indicator for water quality.

Some alternatives for lowering our environmental impact from hydrocarbons and the functional groups include: using organisms like bacteria to attack containments in an ecosystem (bioremediation), biological controls for pests instead of pesticides or herbicides, and manufacturing biodegradable product, reducing sulfur content in fuels, electrostatic

precipitator for dust and pollutant particles in the air, scrubbers in coal-plant smokestacks for acid gases, and catalytic converters for car/vehicle exhaust.

Science 30 Diploma Prep Unit C – Electromagnetic Energy (Physics)

The two major outcomes for this unit are:

1.

explain field theory and analyze its applications in technologies used to produce, transmit and transform electrical energy (13-18%)

2.

describe the properties of the electromagnetic spectrum and their applications in medical technologies, communication systems and remote-sensing technologies used to study the universe. (7-12%)

General Outcome 1

Students will explain field theory and analyze its applications in technologies used to produce, transmit and transform electrical energy.

Fields

Field - a property of space around a mass, an electric charge or a magnet that causes another mass, electric charge or magnet introduced in to this region to experience a force.

In static electricity, like charges repel and opposite charges attract. In addition, charged particles will attract neutral particles with static charges.

We looked in depth at three specific fields: magnetic, electric, and gravitational. We found that a magnetic field produced an electric field and vice versa. This was the principal behind electromagnetic induction.

Magnetic field lines point north-south

Electric: Toward Neg. Away from Positive

Grav: Toward the mass

To calculate field strength we looked electric fields and gravitational fields – know the formulas are similar, but depend on either the mass (gravity) or the charge (electric) with different constants. Students should understand that the strength of an electric or gravitational field is inversely proportional to the square of the distance from the point source of the field. One way for students to visualize this concept is graphically, as shown below. This relationship can be compared with concepts such as half-lives and population growth.

Common mass and radius values are also found in the data book (on p.2)

In addition to field strength, students need to be able to find the force and compare these values to those on Earth. As it states in your data book,

We can find the force due to gravity (N) by multiplying any mass by the field strength.

Circuits

For series and parallel circuits students should focus on calculating resistance and be able to recognize the different symbols used in electrical diagrams.

Understand that using different loads will change the resistance (using a LED light bulb instead of an incandescent)

When the numbers of resistors are kept the same, parallel circuits will have lower total resistance as they have more than one path for the electrons to travel through.

Power, Voltage, Energy, or cost questions will involve the use of the following formulas.

Write down what you are provided and try to solve for the unknown. Remember, Energy can be measured in Joules or kWhours.

Electric current can be measured using a multimeter. For current = ammeter, voltage = voltmeter and resistance = ohmmeter.

*** Look for the variables question (manipulated, responding, and variable) to come from the section on circuits. ***

There is an emphasis on the general design, function, and comparison of motors and generators. Motors use electric current to produce a moving armature. Generators produce electric current by using energy to move the armature. The concept of electrical induction in relation to generators and transformers is important (remember, a moving magnetic field induces an electric current and vice-versa).

Electricity flows in two ways, either in alternating current (AC) or in direct current (DC). The word electricity comes from the fact that current is nothing more than electrons moving along a conductor, like a wire, that has been harnessed for energy. The difference between AC and DC has to do with the direction in which the electrons flow.

In DC, the electrons flow steadily in a single direction, or "forward." In AC, electrons keep switching directions, sometimes going "forwards" and then going "backwards." The power that comes from wall outlets is AC. DC power is used in batteries.

Think of this way:

DC – cannot travel very far until it starts to lose energy but it can provide high power.

AC – can travel safer over longer distance and can provide more power.

Transformers are used to step-up (increase) or step-down (decrease) the voltage based on the number of turns. Remember V=Voltage and I=current. Refer to the data book for the equations:

General Outcome 2

Students will describe the properties of the electromagnetic spectrum and their applications in medical technologies, communication systems and remote-sensing technologies used to study the universe.

Know that the electromagnetic spectrum is from long, low-frequency radio waves through microwaves, infrared (IR) rays, visible light rays and ultraviolet (UV) radiation to very short, high-frequency waves, such as X-rays and gamma rays.

Identify examples of technologies that apply EMR to solve medical, communication, and societal problems:

Ionizing radiation can harm the DNA of an organism so we must take care when working around UV, X-Ray and Gamma Radiation.

X-Rays are used for medical benefits in going through skin and muscle to see bone.

Gamma radiation is produced in nuclear reactions.

 UV radiation on human skin can cause damage to the DNA and cause cancer.

Visible light allows us to see and plants to carry out photosynthesis

Visible light can also be used with fibre optics for communication.

MRI scans use radio waves for soft tissue imaging.

Radio frequencies deal with communication not only on Earth, but to space (satellites)

Infrared can be used for thermal imaging and heat sensing.

The core of the sun produces all forms of the EMR. Luckily not all of it hits us on Earth (or we’d be sterile… then dead)

Recognize that Earth’s atmosphere absorbs certain frequencies of EMR. Gamma rays, x-rays, infrared and most UV rays are blocked by the atmosphere. Visible light and radio waves are able to penetrate the atmosphere the best. If travelling in space, astronauts and equipment have to take into account gamma ray radiation with their suits and coatings.

EMR Waves

Investigate and describe, qualitatively, the phenomena of reflection, refraction, diffraction and polarization of visible light.

The universal wave equation v = λ f works for all waves. We looked specifically at EMR and realized that ALL EMR travels at the same speed = 3 X 10 8 m/s = c.

So for EMR the formula is c= λ f.

Astronomy

A spectroscope can be used to determine the composition of incandescent objects or substances, and is a device that lets us find out what things are made of. It works by taking light and splitting it up into its component colors. Different elements make different colors when they glow. We can make objects and gasses glow by heating them up in a flame, or by passing electricity through them. The spectroscope spreads out the colors of the light, and we can identify the elements by the bright lines we see in the spectroscope.

In working with stars we either produce different types of spectra:

Emission (bright line) - element is heated it will produce bright lines on a dark background.

Absorption (dark line) - Gives the composition of stars with dark lines when it passes through a cool gas. Spectral Analysis used this type of spectra.

Spectroscopy allows us to find out two main things about stars:

• The composition of a star (what elements make it up) and its temperature

• The direction the star is moving based on Doppler shifting (red-shifting away. Blueshifting towards).

Evolution of stars:

Low Mass Stars (Our sun or smaller than our Sun)

Gas & dust  low mass star  red giant  expanding shell of gas (nebula)  white

dwarf (dense)

Intermediate – Mass Stars (1.4 – 8x Sun’s mass)

Gas & dust  intermediate mass star  supergiant star  supernova (implosion) 

neutron star (super-dense)

High Mass Stars (8x Sun’s mass)

Gas & dust  high mass star  supergiant  star collapses supernova  dense black hole (EXTREMELY DENSE!)

Science 30 Diploma Prep Unit D – Environment and Energy

The two major outcomes for this unit are (20-30%)

Students will explain the need for balancing the growth in global energy demands with maintaining a viable biosphere.

Students will describe the sun as Earth’s main source of energy and explain the functioning of some conventional and alternative technologies that convert solar, nuclear, tidal and other energy sources into useable forms.

General Outcome 1

Students will explain the need for balancing the growth in global energy demands with maintaining a viable biosphere.

Recognize the energy consumption of contemporary society with that of traditional cultures and Aboriginal societies has increased exponentially over the past 150 years. Canada’s per-

capita energy consumption is much greater than most developed and developing countries as it is affected by factors such as economy, lifestyle, level of technology, geography, and climate. Energy consumption is greater than it has ever been in the past and continues to grow as markets like the United States, China, and Canada use more and more energy.

Be able to come up with ideas for sustainable development to increase the efficient use of energy. This could be efficient use of energy in the home, in industry and in transportation.

Realize there may be short-term economic downsides that limit these actions in our world.

We broke energy sources down into two main categories non-renewable and renewable power.

Non-Renewable: Fossil Fuels (petroleum, natural gas, and coal), Nuclear Power

Remember the difference between non-renewable and renewable sources of energy is the ability of the resource to be sustained over a lifetime. For instance, trees are considered renewable because as you use them they are able to be replanted and grown to achieve sustainability. Fossil fuels take millions of years and cannot easily be sustained.

Fossil fuels are the primary source of energy of our world today. They are relatively cheap and produce a large amount of energy. However there are problems:

Fossil fuels are running out (sustainability numbers have between 50-200 years left of things like coal/oil)

Environmental pollutants contribute to greenhouse gasses, acid rain, and smog.

Environmental damage to the land and water in mining and extraction (i.e. oil spills, strip mining, etc).

Nuclear energy is a descent alternative as the amount of energy produced by uranium is substantially more than fossil fuels and we have a large enough supply of uranium to sustain our development for the time being. Nuclear energy does not produce greenhouse gases, acids raid, or smog. However, there are problems:

Radioactive waste material – needs to be protected and stored for hundreds of years

Possibility of nuclear meltdown or terrorist attack.

General Outcome 2

Students will describe the sun as Earth’s main source of energy and explain the functioning of some conventional and alternative technologies that convert solar, nuclear, tidal and other energy sources into useable forms.

Alternative Energy Sources (Renewable): Solar, Wind, Geothermal, Biomass (ex. ethanol),

Hydrogen Fuel Cells, Hydroelectric, and Tidal. KNOW THE ADVANTAGES, and

DISADVANTAGES for each.)

Solar radiant energy also is the primary source of energy of :

Solar – Both with passive and active types (know the term

photovoltaic cells)

Wind – heating up Earth and driving water cycle to create wind currents

Biomass – as the original source of energy for plants to use photosynthesis.

Hydroelectric - he Sun evaporates water from the sea and lakes, which forms clouds and falls as rain in the mountains, keeping the dam supplied with water

*Fossil Fuels – as organic matter used the energy produced from the sun and photosynthesis to survive (*note – fossil fuels are non-renewable).

Other Sources of Energy

Hydroelectric and Tidal forces use gravitational forces.

Nuclear energy and geothermal and both are powered by radioactive decay.

There will be more emphasis on biomass and hydrogen fuel cells than found on previous assessments for this diploma.

Biofuel or biomass is a renewable energy source. It is biological material derived from living, or recently living organisms. Biomass is commonly plant matter grown to generate electricity or produce heat.

The most conventional way on how biomass is used however, still relies on direct incineration (i.e. burning).

Examples of biofuels include ethanol used as a gasoline additive, biodiesel made from vegetable oils and fats. Biomass includes dead plant material or gases released from garbage or waste material.

Advantages: Theoretically inexhaustible fuel source, there is minimal environmental impact compared to fossil fuel burning, efficient, viable, and

 relatively clean-burning and it is available throughout the world.

Disadvantages: Still producing CO2 greenhouse gas (though values are “net-

neutral” since more crops are planted to photosynthesize the additional CO2) and it is still an expensive source, both in terms of producing the biomass and converting it to alcohols for most places.

Hydrogen Fuel Cells - Hydrogen is high in energy, yet an engine that burns pure hydrogen produces almost no pollution. A fuel cell combines hydrogen and oxygen to produce electricity, heat, and water. Fuel cells are often compared to batteries. Both convert the energy produced by a chemical reaction into usable electric power. However, the fuel cell will produce electricity as long as fuel (hydrogen) is supplied, never losing its charge. Fuel cells are a promising technology for use as a source of heat and electricity for buildings, and as an electrical power source for electric motors propelling vehicles.

Advantages of Hydrogen

 Hydrogen is a very clean fuel that produces minimal emissions

 Whey hydrogen is used in a fuel cell, the only byproducts are heat and water and

 cutting down on CO2 and air pollution

Typical gasoline powered cars only use about 20% of the fuel to power the car. With hydrogen fuel cell cars, around 40-60% of the fuel is used to power the electric motor.

Disadvantages of Hydrogen

 The technology to produce, store, and transport hydrogen power at an efficient cost is not yet available and will not likely be for a long while.

 It takes more energy to make Hydrogen than you get from it at this time.

 A hydrogen fuel cell car will not be able to travel as far on a tank of fuel as a traditional gasoline powered car. The fuel cell cars are not equipped to store the amount of hydrogen needed for long distances, so you would need to fill up more often.

 If you live in an area where the temperature gets down to freezing, you might have a

 problem with your hydrogen fuel cell car. Since these cars have water in the fuel cell system constantly, there is a risk it could freeze. Also, the hydrogen fuel cell car has to be at a certain temperature to perform well.

Hydrogen is highly explosive!

Calculating Energy or Thermal Heat

Energy produced from greatest to smallest is by nuclear, chemical, and phase changes.

Students should be able to distinguish clearly between alpha, beta, and gamma decay reactions.

Energy produced in chemical combustion reactions (usually with hydrocarbons), will use standard heats of formation in your data book to find the energy. Fission, fusion, and decay reactions produce energy according to the mass-energy equivalency. Figure out first if you are using a combustion or a nuclear reaction.

Amount of Energy Produced:

Phase <

Combustion

<

Fission

<

Fusion

Explain the difference between fission and fusion and balance simple nuclear reaction equations to show the conservation of nucleons.

Nuclear reactions are always conserved.

Remember the top number is the number of nucleons (neutrons and protons)

The bottom number is the atomic number (number of protons)

So in any reaction the reactants top numbers must equal the products top numbers. Same goes for the bottom.

Example:

Fission Reactions – split nuclei apart. Found in CANDU nuclear reactors and atomic bombs.

Release large amounts of energy. Most common is the fission reaction of uranium-235.

Fusion Reactions – fuse nuclei together under incredible temperature and pressure. Found in stars to make heavier elements and release even larger amounts of energy. Current research into the possibility of fusion reactions as an energy source (the first prototype plants are just being built to test the possibility of this… energy source is a long way off, if ever)

Types of Major Power Plants

Fossil fuel plants will use coal, natural gas, or oil as a chemical fuel source to heat up water into steam that powers a turbine to move and generate electricity.

Hydroelectric will turn a turbine by the moving water setup by a dam.

Nuclear power stations will generate heat by setting off a nuclear fission chainreaction with uranium in water to heat up the water into steam that powers a turbine to move and generate electricity. The CANDU reactor in Canada operates under this principle.

Environmental and Health Problem Cause – Effect

Know the basics about each major environmental/health problem and the primary chemicals responsible.

Global Warming / Climate

Change / Drought

Major Cause

Increased fossil fuel burning

Primary chemical

CO

2

Ozone depletion from industry and transportation.

Use of dangerous halogenated hydrocarbons

CFC and other halogens

Used Uranium/Plutonium Radioactive waste Used in nuclear plants as spent fuel rods

Cancer / DNA Mutation Increased exposure to ionizing radiation

Acid Deposition

UV, Gamma, X-Ray

Radiation. Also some organic compounds like

Benzene, DDT

SO

2

, NO

2

, and sour gas (H2S).

Resistant Pathogens

Burning of sulfur and nitrogen oxides

Overuse of chemicals can cause resistant strains of unwanted organisms.

Benzene/organic compounds that don’t break down.

Antibiotics / pesticides

Biomagnification

(Photochemical) Smog

Increased concentration through the food chain.

Air pollution caused from the burning of fossil fuels.

DDT, heavy metals like mercury

Particulate matter (soot),

SO2, NO2.

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