End of Year Review 2014 with notes - Ms. Jadah's Virtual ...msjadah.weebly.com/uploads/1/1/4/1/11418827/10... · End of Year Review 2014 with notes 6 Chapter Five: Electricity and

End of Year Review 2014 with notes

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Science End of Year

ExamReview

Chapter One: Atoms and Elements

1. The Atom

History of the Atom• Dalton's Atomic Model: Atoms are solid, indivisible balls of

different masses

• Thomson's Atomic Model: Saw the atom as a blueberry muffin (muffin dough is positively charged while blueberries are embedded in them that are negatively charged electrons)

• Rutherford's Atomic Model: A small, dense, nucleus contains the entire positive charge of the atom, while electrons are scattered randomly in a large space around the nucleus.

• The RutherfordBohr Atomic Model: Consists of a very small nucleus surrounded by electrons moving in a series of orbits.

Chapter One: Atoms and Elements3. Periodic Table


A row (period) tells us how many shells an element has.

A colum (group) tells us how many valence electrons an element has.

Metals are to the left of the staircase, nonmetals to the right and metalloids along the staircase.

Group 1: Alkali MetalsGroup 2: Alkaline Earth MetalsGroup 7: HalogensGroup 8: Noble Gases


Representing Atoms

Lewis Dot Notation: (Only look at valence electrons)

Oxygen: Boron:

O B RutherfordBohr Model:Oxygen:

8+

Simplified Atomic ModelCarbon:

6 p+2 e 4 e



2

IonsAn ION is an atom that has become electrically charged by losing or gaining one or more electrons.

How do we know whether an atom will gain or lose electrons?They want to become like the noble gases, they want to become stable and have full valence electron shells.

P. 42 - 43

Lithium:

3 p+2 e 1 e

Ion form:

3 p+2 e

Oxygen:

8 p+2 e 6 e

8 p+2 e 6 e

As an Atom:

Chapter Two: Molecules and Solutions

1. How did Beryllium become Be+2? a) It gained 2 electronsb) It gained 2 protonsc) It lost 2 electrons d) It lost 2 protons

2. What has happened to a posive ion? a) It has lost electrons b) It has gained electrons c) It has lost protons d) It has gained protons

3. How many protons and electrons does N‐3 have?

IonsChapter Two: Molecules and Solutions

Solutions and ConcentrationAn aqueous solution is a solution with water. (Ex; Water and Salt)

1% = 1 (g or ml)100 (ml or g)

? ppm = ? g 1000L

ml L

- 1000

x 1000

? mg1 L? ppm = OR



3. Analysis of a 25 L sample of well water shows that it contains 6 mg of dissolved arsenic.What is the concentration in ppm of dissolved arsenic?

1% = 1 (g or ml)100 (ml or g)1 ppm = 1 g 1000L 1 mg1 L1 ppm = OR

ml L

- 1000

x 1000

1. Calculate the concentration (g/L) if 30 g are dissolved in 250 ml of solution.

2. What is the PPM concentration if 0.06 g are dissolved in 3000 ml of solution?

Lab Exam?

1. Your task is to create a 100 ml solution that has a 17% concentration of salt.

2. Create a 275 ml solution that has a 29% concentration of salt.

Electrolytes

An electrolyte is a substance that allows an electric current to flow through the soluon (when it's dissolved in water).

Acids: Releases H+ ions. Starts with HEx: HCl and H2SO4

Bases: Releases OH‐ ions. Ends in OHEx: NaOH and Mg(OH)2

Salts: Produced by the chemical bonding of a metal and non‐metal. Ex: NaCl and AgNO



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Electrolytes: PHPH Scale ranges from 0 to 14If the PH level is less than 7, the solution is acidicIf the PH level is 7, the solution is neutral. If the PH level is greater than 7, the solution is basic.

or Basic

The difference of one unit between two substances actually indicates that one of the substances is 10 times more acidic than the other.

For example, a solution with a pH of 3 is ____ times more acidic than a solution with a pH of 4.

A solution with a pH of 9 is ____ times less basic than a solution with a pH of 11.


Energy

a. The Law of Conservaon of Energy : Energy cannot be created nor destroyed; it can only be transferred or transformed.

b. Energy efficiency: the percent of energy consumed by a machine or system that was transformed into useful energy.

Energy efficiency = Amount of useful energyAmount of energy consumed x 100

Example: A fluorescent light bulb uses 100 joules of electrical energy. 25 Joules is light energy, how energy efficient is this light bulb?

Chapter Three: Different Forms of Energy

Chapter Three: Different Forms of Energy

Thermal Energy: Thermal energy is energy from fire, the sun or a heang element.

It comes from the random movement of all the microscopic parcles in a substance. As the temperature increases, there are more parcles and increased thermal energy.

Heat: The transfer of thermal energy between two environments with different temperatures. Heat always pases from the warmer to the cooler environment.

Temperature: The measure of the degree of agitaon of the parcles of substance.

Chemical ChangesThe Law of Conservaon of Mass (Maer)

The total mass of reactants is always equal to the total mass of products.

p.110

Before the reaction After the reactionDuring

CH4 + 2 O2 CO2 + 2H2O 16 g + 64 g 44 g + 36 g

C OOH

O

H

H

O

H

O OC

H H

H

HO O

Example: Which of the following examples below can be used to verify the Law of Conservation of Mass?

a) 5 g + 11 g > 12 g + 4 g

b) 12 g + 8 g > 6 g + 15 g

c) 24 g > 11 g + 13 g

Chapter Four: Changes in Matter

Types of Chemical ChangeChapter Four: Changes in Matter

Acid‐Base Neutralizaon : a chemical change involving the reacon of an acid with a base, producing a salt and water

Oxidaon : a chemical change involving oxygen (or with properes similar to oxygen)

Combuson : a form of oxidaon that releases a large amount of energy


Types of Chemical Change


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Cellular‐Respiraon : a chemical change where glucose and oxygen are used to generate energy, the reacon also produces carbon dioxide and water

Sugar + Oxygen > Energy + Carbon Dioxide + Water

Photosynthesis: a chemical change that produces glucose and oxygen from solar energy, carbon dioxide and water.

Solar energy + Carbon Dioxide + Water > Sugar + Oxygen

Types of Chemical Change


Photosynthesis

Solar energy + Carbon Dioxide + Water > Sugar + Oxygen

Sugar + Oxygen > Energy + Carbon Dioxide + Water

Signs a chemical change has occured: ‐ release of gas‐ emission or absorpon of heat‐ emission of light ‐ a change in colour ‐ the formaon of a precipitate

Ex: baking bread, burning wood

Does not alter the nature or the characteriscs of maer. The atoms and molecules of the substance do not change.

Ex: chopping wood

Chapter Four: Changes in MatterBalancing Chemical Equations

1. _____ H2 + _____ O2 _____ H2O _____ H3PO4 _____ H4P2O7 + _____ H2O


Negavely Charged Bodies: have more electrons then protons

Posively Charged Bodies: have less electrons then protons

Remember that the number of protons never changes! Substances can only lose or gain electrons.

Conductors allow the free flow of electrical charges

Insulators hinder the free flow of electrical charges

Chapter Five: Electricity and Magnetism

+ + +If A is negatively charged, what charge does C have?

If A is positively charged, what charge does D have?

Opposite charges aract Like charges repel

A B B C

A B B C C D



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Static ElectricityMost objects and substances are neutrally charged (same number of protons and electrons)

Objects can become posively (+) charged by losing electrons

Objects can become negavely (‐) charged by gaining electrons

Tendency to gain electrons(acquire a negative charge)

Tendency to lose electrons(acquire a positive charge)

Plastic

Nickel

Paper

Silk

Wool

Glass

What charge will each substance acquire when plastic and wool are rubbed together?

Plastic Wool

What about wool and glass? Wool Glass


Static ElectricityChapter Five: Electricity and Magnetism

Three methods to charge an object:

• Friction: Starts with two neutral objects, and the friction pulls electrons away from one of the objects and transfers them to the other. Afterwards there are two objects with opposite charges.

• Conduction: Starts with one charged object and one neutral object. The charge of one object is shared between two objects when they come into contact. Afterwards there are two objects with like charges.

• Induction: Starts with one charged object and one neutral object. The closeness of the charged object causes the charges in the neutral object to separate. Afterwards you have one charged object and one object carrying a partial positive charge on one side and a partial negative charge on the other side.

+

++ + +

+ +++

+

Ohm's Law

V = IR

where V is potential difference (in )

I is Current Intensity (in )

R is Resistance (in )

Electrical Power

P = VI

where P is Electrical Power (in )

V is Potential Difference (in )

I is Current Intensity (in )

Chapter Five: Electricity and Magnetism Chapter Five: Electricity and Magnetism

Energy Consumed

E = P∆t

where E is Energy Consumed (in )

P is Electrical Power (in )

∆t is time difference (in )

Other units for Energy consumed:

joules = watts x seconds

watt‐hour = watts x hour

kilowatt‐hour = kilowatts x hour

E = P t


A strategy for your test

On your formula sheet, list all possible variables and their units.


An electrical circuit is a network in which electrical charges can flow continuously in a loop. If the electrical charges cannot flow continuously in a loop the circuit will not work.

Circuits need the following components to work: • A power supply: creates a potential difference (ex: battery)

• Electrical resistance: Something that uses electrical energy (ex: light bulb or resistor)

• Wires: carries the charges from the power supply to the elements and then back to the power supply.

Circuit Diagrams Important Symbols:

One battery

Two batteries

Light bulb

Resistor

Voltmeter

Ammeter

Switch (On position)

Switch (Off position)


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Ammeters are always placed within the loop.

Voltmeters are place 'out of' the loop, with the element they are finding the potential difference of.

Ammeter vs Voltmeter


Series vs Parallel

A circuit where the components are connected end to end (in one big loop).

A circuit that branches out at least once (or has multiple loops).

Electrons have one path to follow (from negative to positive) If one light bulb burns out, no other light bulbs in a series circuit will work.

Electrons have multiple paths to follow If one light bulb burns out, the others can still work

Conventional Current Direction: from the positive terminal of the power supply to its negative terminal.

+ to

Electron flow: electrons travel from the negative terminal of the power supply to its positive terminal.

to +

Chapter Five: Electricity and MagnetismMagnetism

Magnets contain Iron (Fe), Cobalt (Co) and/or Nickel (Ni).

All magnets have a North Pole and a South Pole. These are formed when electrons of a magnet rotate in the same direction. Electrons in nonmagnetized objects rotate in opposite directions.

Opposite Poles Attract

Like Poles Repel

S N N SS N N S

S N N S N S S N


Magnetism: Magnetic Fields

A magnet's force affects a limited area around the magnet. This area is called the magnec field. The magnec field has lines which point OUT OF NORTH and INTO THE SOUTH.

s N

s N s N

Magnetism: Compass

A compass contains a small magnet with a North Pole and a South Pole.

When a compass is placed next to another magnet, the compass's NORTH POLE will point to the SOUTH POLE of the other magnet,and the SOUTH POLE will point to the NORTH POLE along the magnec lines.

s N

NS

s N

N S

Chapter Fourteen: Electrical EngineeringPower Supply For an electrical or electronic circuit to operate, it needs a power supply. The power supply provides the energy that makes a current flow through the wires and components of the circuit. Each type of power supply has advantages and disadvantages.

Some examples of power supplies (see page 463 for more details)

Battery Electrical Outlet Solar Cell (Photovoltaic Cell)

Chapter Fourteen: Electrical Engineering

• Conduction is an electrical function performed by any component that can transmit electric current from one part of a circuit to another.

Best wires for conduction are shorter, thicker and made of copper.

• Insulation is the electrical function performed by any component that prevents an electric current from flowing.

• Protection is the electrical function performed by any component that can automatically cut current flow in the event of a power surge. (Ex: fuses and breakers).

Electrical Functions:


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Chapter Fourteen: Electrical Engineering

• Control

A closed circuit is a circuit in which electric current flows in a loop.

An open circuit is a circuit in which electric current cannot flow in a loop.

Switch at 'off' position.

Control is the electrical function performed by any component that can open and close a circuit (such as a switch).

• Transformation of Energy

Electrical function performed by any component that can convert electrical energy into another form of energy. (Ex: A lightbulb)

Electrical Functions (cont'd):

Chapter Six: The Lithosphere and the Hydrosphere

The lithosphere consists of the Earth's crust and the topmost part of the upper mantle, two layers forming the external structure of our planet.The lithosphere contains minerals and rocks that have been essential to the development of human civilization.


Minerals are solid substances with clearly defined properties.

Properties of Minerals:

Hardness (resistance to scratching, given a value from 1 to 10 which is Mohs scale)

Colour (what is the colour of the mineral)

Transparency (does is allow light to pass through?)

Streak (powder trace obtained by rubbing the mineral on a surface of porcelain)


Rocks are solids composed of many minerals. Types of rocks: • Igneous Rocks: created through cooling of magma.

Extrusive Igneous Rocks: formed above the surface (with contact with air) Intrusive Igneous Rocks: formed below the surface

• Sedimentary Rocks: created by sediments (pieces) of other rocks forming together.

• Metamorphic Rocks: created by former igneous or sedimentary rocks that have been transformed by heat or pressure.

Ore is a naturally occurring mineral containing a valuable constuent (as metal) for which it is mined and worked.


Permafrost: soil with a temperature of 0oC or below for two or more years

In some areas, the top layer of soil thaws during the summer and freezes again during the autumn. This top layer is called the active layer.

As permafrost melts, it can cause damage to contruction and roads.

Also, permafrost has a lot of carbon trapped in it, so when it melts, the carbon is released into the atmosphere in the form of methane.

Chapter Six: The Lithosphere and the HydrosphereEnergy from the Lithosphere

Geothermal Energy

Advantages Disadvantages

‐ Generates few greenhouses gases

‐ Renewable energy source

‐ Installaon is very expensive

‐ Not available everywhere

Fossil Fuels (Coal, Natural Gas and Oil)

‐ Currently set up to use fossil fuels

‐ Readily available

‐ Emits greenhouse gases

‐ Nonrenewable energy source

Nuclear Energy ‐Requires few resources for a large amount of energy

‐ Inexpensive

‐ Risk of nuclear accidents

‐ Produces dangerous radioacve waste

‐ Nonrenewable energy source (comes from Uranium)


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A watershed is an area of land whose lakes and rivers all empty into the same larger body of water.

Many aspects of the surrounding land and climate can affect how water flows within a watershed, either slowing down the flow by placing obstacles in the water's path or accelerang the course.

The following are a few examples of these factors:

‐ topography: the shape, slope and terrain of the area‐ geology: the type, depth and structure of the rock. ‐ climate: rain or snowfall, winds and temperature. ‐ vegetaon : its density and diversity‐ agriculural, industrial and urban development


Important Parameters in the study of Oceans: These factors affect Thermohaline Circulation

• Water Temperature > The water temperature of oceans is influenced by the

following parameters:– Depth – Seasons – Latitude

• Salinity> The salinity (concentration of salt in the water) of oceans is

influenced by the following parameters:– Heat and Drought– Melting Pack Ice and Glaciers

Chapter Six: The Lithosphere and the HydrosphereSurface CurrentsSurface currents are mostly wind driven. These currents move horizontally, usually in the first 400 m of water below the surface.

Subsurface CurrentsAt depths of more than 800 m, winds no longer affect ocean circulaon. Deep currents prevail here.

Thermohaline CirculationSurface and subsurface currents are closely interconnected and form a huge conveyor belt that moves water all around the world. This movement is called thermohaline circulaon .

It is responsible for major transfers of heat around the world. Without it, the differences in temperature between the equator and the poles would be much more dramac.

The Cryosphere is the poron of the Earth's surface where water is found in solid form. It consists of pack ice, glaciers, frozen lakes and rivers, vast expanses of snow and the ice in permafrost.

Pack Ice: ice floating on the oceans near the North and South Poles

Glaciers: a mass of ice on land formed by compressed snow



Hydraulic Energy

Energy produced from moving water.

Advantages: Renewable Resource Does not emit greenhouse gases

Disadvantages: Can be harmful to the environment (cause flooding/changes the

land) Expensive

Chapter Seven: The Atmosphere

The atmosphere is a layer of air that envelops the Earth. It is made up of gases that are essenal to life on our planet.

The gases of the atmosphere are essenal for the following reasons:

1) They act as a screen, blocking out dangerous rays from the sun, such as ultraviolet rays.

2) They ensure a relavely stable climate on Earth by retaining heat.

3) They include oxygen (which is necessary for cellular respiraon) and carbon dioxide (which is necessary for photosynthesis in plants).

The atmosphere: 78% is Nitrogen21% is Oxygen 1% is Water, Argon, Carbon Dioxide


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Low Pressure Area

Fewer Gas Molecules

Cooler Temperatures

High Pressure Area

More Gas Molecules

Warmer Temperatures

What is wind?


What is an Air Mass? Air that remains over a large area for a period of me and has a uniform temperature and humidity.

The characteriscs of an air mass depend on where they were formed.

An air mass can be: Connental Air Mass ; forms over land, forms a dry air massor Marime Air Mass ; forms over water, forms a moist air mass

Tropical Air Mass; forms near the equator, forms a warm air massor Polar Air Mass; forms near the poles, forms a cold air mass

Chapter Seven: The AtmosphereWhat happens when a cold air mass meets a warm one?Cold Front Warm air rises rapidly and cools, which produces puffy clouds, wind, and heavy rain.

What happens when a warm air mass meets a cold one?Warm Front Warm air rises gently which brings cloudy weather and moderate, steady showers


A cyclone is a tropical storm characterized by violent winds revolving around an area of low pressure. These cyclones are also called hurricanes or typhoons.

Chapter Seven: The AtmosphereGreenhouse Gases: CO2 ‐ Carbon DioxideCH4 ‐ Methane

N2O ‐ Nitrous Oxide

The greenhouse effect is a natural process that allows the Earth to retain some of the heat it receives from the Sun.

Intensification of Greenhouse Effect


Wind EnergyThe movement of gas molecules from high pressure areas to low pressure areas creates wind.

Wind energy can be transformed into electrical energy.

Solar EnergyEnergy from the sun can also be transformed into electrical energy.

Low Tide

Low Tide

High Tide High TideMoon

Tidal EnergyEnergy from the flow of tides.


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Chapter Seven: The AtmosphereEnergy from the Atmosphere

Wind Turbines

Advantages Disadvantages

‐Renewable Resource

‐ No producon of greenhouse gases

‐Visual polluon (ugly)

‐ Cannot predict how or when wind will blow.

‐Wind energy cannot be stored.

Solar Energy


‐ No producon of greenhouse gases

‐ Supplies electricity to isolated areas

‐Costly system (it's expensive)

‐ Amount of energy produced varies with the Sun's posion and cloudy condions.

Tidal Power Plants


‐ Reliable source of energy

‐ Does not emit greenhouse gases

‐ Complex plants

‐ Costly system (it's expensive)

‐ Suitable sites are rare (dal range but be at least 5 m)

Chapter Eight: The Biosphere

The Carbon Cycle

Chapter Eight: The Biosphere

The Nitrogen CycleChapter Eight: The Biosphere

Biomes

Factors determining terrestrial biome distribution:

• Latitude• Altitude• Temperature *• Precipitation *• Soil Type• Solar Energy• Winds • Proximity to water

Factors determining aquatic biome distribution:

• Salinity * • Turbidity (Water Clarity)• Temperature• Direction and strength of current

• Presence of oxygen and carbon dioxide

• Solar energy• Nutrients • Water Depth

Chapter Nine: Populations and Communities

Over me, the size of a populaon may increase, decrease, or remain stable. Four factors explain these changes:

Births: Births of individuals within a populaon Deaths: Deaths of individuals within a populaonImmigraon : Arrival among the populaon of individuals from other regionsEmigraon : Departure of individuals to other regions

Chapter Nine: Populations and CommunitiesHow can scientists and ecologists measure population size?

Method 1: Counting IndividualsWhen possible, the size of a population can be measured by counting all individuals within the area of occupied by that population.

Method 2: Counting by Sample AreaThis method is counting the individuals in randomly selected sections of the study area and then estimating the total population size with the following calculation:

Population Size = Average # of individuals per section x Total study areaArea of section


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Method 3: Mark and recapatureThis method is commonly used to estimate the population size of very mobile animals (such as birds, fish, and mammals that are widely scattered within their habitats.

This method has several stages: • Installing cages or nets in areas inhibited by the population• Counting the captured animals and marking them with tags, rings, collars or dabs of

paint• Releasing the marked animals so they mix with unmarked individuals in the

population• Reinstalling cages or nets• Counting captured individuals a second time, with a separate count for marked

individuals• Estimating the size of the population using the following calculation:

Population Size = # of marked animals x Total # of animals captured the second time# of marked animals recaptured

Chapter Nine: Populations and CommunitiesPopulation DistributionThe individuals that make up a population are distributed in different ways within the space they inhabit.

Clumped DistributionMost common pattern of distribution, where individuals form groups. Often observed when certain areas of population's habitat offer better living conditions.

Uniform DistributionPattern of distribution in which individuals are dispersed equally throughout the population's habitat. Often due to competition for natural resources.

Random DistributionPattern of distribution rarely found in nature, in which individuals are randomly and unpredictably dispersed across the population's habitat.



Abiotic Factors Biotic Factors

Amount of light Soil or water pH Terrain Depth of Snow Temperature Air humidity

Birth rate Disease Amount of food Predation Competition Human activity

A limiting factor is ...

Biological Cycles in PopulaonsIn the wild, some species repeatedly experience periods of growth in their population size, followed by periods of decline. These populations follow patterns called biological cycles.


Communities: BiodiversityBiodiversity describes the variety of species living in a community.

To measure the biodiversity of a community, we must look at two things: • the number of species in the community (also known as species richness) • the relative abundance of each species, meaning the number of individuals

of a particular species in relation the total number of individuals in the community.

The biodiversity of a community is high when: • the number of species is high• the relative abundance of different species is similar


Which community has the higher biodiversity and why?



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Within a community, individuals and populations establish various relationships with each other and their environment.

The four main types of interaction are:

Competition

Intraspecific Competition: which occurs between the individuals of the same species

Interspecific Competition: which occurs between the individuals of different species

Predation (and Parasitism)

Mutualism

Commensalism

Chapter Nine: Populations and Communities Chapter Ten: Ecosystem

What is an ecosystem?

Level 1: Individual

Level 2: Populaon (Same species, in one area)

Level 3: Community (Many populaons in one area)

Level 4: Ecosystem (A community of living organisms interacng with one another and with the nonliving components of the environment they inhabit).

Chapter Ten: Ecosystem

Interactions within an ecosystemTrophic Relaonships

The posions of each organism in a chain corresponds to its TROPHIC LEVEL. Food chains contain the following trophic levels: • producers• consumers• decomposers

Producer >

Consumer Consumer ConsumerConsumer

Decomposer


Interactions within an ecosystem

Trophic RelaonshipsMore than one food chain is possible in an ecosystem. For example, various animals can graze on the grass in a forest and these animals can be eaten by a number of different predators. An ecosystem thus contains many trophic relaonships.

A representaon of all these relaonships is called a Trophic Network or a Food Web.


Decomposers Detritus

Environment

Consumers

Producers

Flow of inorganic matterFlow of organic matter

Matter flow in an ecosystem

Energy flow in an ecosystem

Energy is lost in which two ways? Biomass

The biomass is the total mass of organic maer (plant and animal) in an ecosystem at any given me.

New organic maer is generated by producers. This maer is the new biomass of the ecosystem. Measuring the amount of new biomass reveals the primary producvity of the ecosystem.

Chapter Ten: EcosystemThe Primary Producvity of an ecosystem is the amount of new biomass generated by its producers.

Factors that affect primary producvity:• the amount of light because the radiaon

energy of the sun is necessary in photosynthesis

• the amount of water available because water is also necessary for photosynthesis

• access to essenal nutrients for producers, especially carbon, nitrogen, phosphorus and potassium

• the temperature because some weather condions promote the growth of producers


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Natural DisturbancesThese are events triggered by environmental phenomena rather than by humans, but they sll damage an ecosystem.

Examples of natural disturbances are storms, volcanic erupons, forest fires, droughts, floods, periods of frost and heat waves.

Human DisturbancesHumans remain the principal source of environmental disturbances on Earth. Many human acvies have a damaging effect on ecosystems, from individual acts like liering to large scale objects like logging operaons that disrupt forest ecosystems, or oil spills at sea which can harm organisms living in marine ecosystems. Mining is another example of a human disturbance in an ecosystem.

Aer suffering a disturbance, an ecosystem will undergo a series of gradual changes, somemes spread out over hundred of years unl it regains a state of balance. This series of changes in an ecosystem is called ecological succession.

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End of Year Review 2014 with notes - Ms. Jadah's Virtual ...msjadah.weebly.com/uploads/1/1/4/1/11418827/10... · End of Year Review 2014 with notes 6 Chapter Five: Electricity and