Grade 9 Science Year in review 2013/2014

These are the KEY points you have to know for the exam. They are your Key Essentials that the exam questions are most likely based on.

General Science

Labs Variables –Manipulated – what you change – what you are testing for –Responding – what happened due to the manipulated variable changing (what you are measuring) –Controlled – what you have to keep the same throughout the experiment

Graphs Graphs show data Relationships on graphs Not all graphs start at zero or increase A B A A A A BB BB A B

Environmental Chemistry

Chemicals in the Environment Nutrients – required for all animal growth –Absorbed by organisms and into cells by diffusion –Organic (contains carbon) Carbohydrates – from grains & makes energy Proteins – for body growth Lipids (Fats) – energy storage – fat & oil Plants produce sugar (sucrose) and O 2 through Photosynthesis –Inorganic Minerals

Fertilizers – required for plant growth - Nitrogen - Phosphorus - Potassium

Problems in the Environment & Food –Pesticides, herbicides, insecticides, fungicides E.g. DDT - affect more than what they are intended to do – Bioaccumulation / Biomagnification Food Chain Increased concentrations over life of organism

Acids & Bases Properties of Acids & Bases pH scale –0 to 14 –7 is neutral –<7 is an acid –>7 is a base –Further away from 7 the stronger it is Acid – sour Base – bitter, slippery - soaps Indicators –Through a color change show strength E.g. Litmus paper; red = acid, blue = base Neutralization – when one reacts with the other –Acid + base Salt + water + ??? Acid neutral Base strong weak weakstrong

Pollutants Toxicity –Acute vs. Chronic Short term or long term to effect something LD50 – Lethal Dose 50% –The dose of a chemical that will kill 50% of the population to which it was applied PPM – parts per million

Water Pollutants Point source –Coming from one definable location Non point source –Location of origin not known Dispersion – diluting pollutants in water –spreading out. Indicator tests –DO 2 – dissolved oxygen (factors affecting) Temperature - T DO 2 Aeration – rapids, waves, etc –Phosphates – enhances growth –Nitrates – growth –Biological indicators (good, poor water) –pH – neutral is good

Biodiversity Bio-indicators – their changes in numbers show changes in water quality Greatest diversity is in high DO 2 and neutral pH.

Landfills –Sanitary vs. secure –Leaching of chemicals Further away it gets diluted 4R’s –Reduce, Reuse, Recycle, Recover Biodegradable –Long term decomposition - poor Dry, cold conditions –Short term decomposition - good Wet, warm conditions

Environmental Issues –Energy Conservation Use of less fuels, new sources of energy, efficiency, etc.. –Seen from many point of views (perspectives) Environmental – pollution / litter Political – gov’t, military Economic - money Ethical – should we do it, is it right

Chemistry

Chemicals Safety –Chemical symbols –WHMIS Workplace hazardous materials information system Symbols Gas Flammable Oxidizer Immediate toxin Other Toxic ReactiveBiohazardous Corrosive

Matter –Solid (s), Liquid (l), Gas (g) –Mixtures vs. pure substances Mixtures – mechanical vs. solutions Pure substances – elements & compounds Know flowchart of Matter –Properties Metals are malleable, conductors of electricity, high melting point, …

Changes Physical Change (and properties) –Same substance –Shape –State change (s to l to g) – eg. ice to water –Reversible Chemical change (and properties) –New substance - Gas released (smell or bubbling) Temp change Colour change Precipitate formed Irreversible

Chemical structure Atom –Electrons (-), protons (+), neutrons –Nucleus (protons and neutrons only) Elements –Symbols – e.g. C, O, H, Na, Cl, … –Periodic Table – rows (periods), columns are groups or families (similar properties) Atomic # equals # of electrons or # of protons # of neutrons = Mass # minus atomic # Compounds (Molecules) –2 or more different elements combined E.g. H 2 O, CO 2, NaCl, C 6 H 12 O 6

Chemical formulas Molecular compounds –Share electrons – e.g. Nitrogen Monoxide = NO –Nonmetals only – right of staircase –Use prefixes; mono, di, tri, tetra, … –Solid, Liquid or Gas at room temp. Ionic Compounds –Transfer electrons from one atom to another –Ions (+ or -) – Complex ions on table –Metal & nonmetal combined (metal first) –Solids only at room temperature –Good electrical conductivity in water due to ions –E.g. NaCl – table salt – in water good conductor –NaCl, CaCl2, Ca (CO3)2

Naming compounds Molecular compounds –Use prefixes; mono, di, tri, tetra, … –Prefix show # of each element –“ide” at end Ionic Compounds –No Prefixes used –“ide” at end –Charges in periodic table used to determine how many of each element is in formula Eg: Na is +1 (1 st column) and S is -2 (2 nd to last column) So Sodium sulfide will be Na 2 S as to balance will need 2 Na and 1 S

Chemical Reactions Chemical equations –Reactants Products –2 H 2 (g) + O 2 (g) 2 H 2 O(l) –(g) gas, (l) liquid, (s) solid, (aq) in solution (water) Law of Conservation of Mass –Mass of all reactants equals mass of all products Endothermic –Feels colder – energy gained in reaction - T Exothermic –Feels warmer – energy released in reaction – T

Reaction Rate How fast a reaction will take place Three factors affecting Reaction Rate: –Surface area SA Reaction Rate –Whole (less SA) vs powder (more SA) –Concentration Concentration Reaction Rate –Temperature Temp Reaction Rate

Corrosion Oxidation of metals –A reaction where Oxygen (O 2 ) is used up E.g. Rust on iron - corrosion (exothermic) Combustion Oxidation of organic materials –A reaction where Oxygen (O 2 ) is used up E.g. burning gas CH 4 + O 2  CO 2 + H 2 O

ELECTRICITY

Charges Electric Charges – caused by the movement of electrons (-) –Positive –Negative –Neutral Static electricity – no continuous flow of e - Electrical discharges –Grounding – sparks, lightening Law of Charges –Like charges repel + & +, - & - –Unlike charges attract + & - –Charged attracts neutral + & neutral, - & neutral

Materials in electricity Insulators –Stops flow of Electrons Conductors –Allows flow of electrons Resistors –Slows the flow of electrons

Circuits Pathway for electricity – electrons flow like water Electric Circuits –Large current & voltage Controlled by switches Closed switch means power flows –Circuit diagrams Symbols Working or not ????

Circuits Parallel –Each load has its own path for electricity –Lights stay same brightness (doesn't change) with additional ones added or removed Series –Loads share paths for elec. –Lights get dimmer with additional ones added

Measuring Electricity Current (I) –Unit is the ampere (amp – A) –Flow of electrons (e - ) Voltage (V) –Unit is the volt (v) –Potential difference Resistance (R) –Unit is the Ohm (Ω) –Slows/reduces the flow of electrons Ohm’s Law R = V formula on test I If voltage increases, current will also increase.

Making / Using Electricity Battery (chemical cell) – chemical to electrical –2 different metals (electrodes) & electrolyte solution Thermocouple – heat (thermal) to electrical Resistor – electrical to heat Motor – electrical to mechanical Generator – mechanical to electrical Light bulb – electrical to light (resistor – filament) Solar cell – light to electrical

Electric Motors 4 main parts of a DC motor –Brushes Connect electricity to motor (commutator) –Commutator Changes direction of current every half turn –Armature Electrical magnets that spin –More power - Stronger magnets - more coils - Closer magnets - more current –Permanent magnets

Electric generators Opposite of a motor –Magnet moves past a coil of wire –More Power Move magnet faster More wire coils Stronger magnets

Electric Safety Prevent overheating, shock, and appliance damage –Fuses One time use, wire burns out (need to replace) Interrupts the flow of electrons –Circuit breakers Automatic switch – turns off with too much current

Electricity Calculations Efficiency Efficiency = Output (useful) E x 100% Input (total) E Power (P) Power = Energy time Cost Cost = kWh (usage) x $/kWh Formulas given on test

Electricity & Environment Efficiency and conservation –Using energy efficient appliances E.g. Florescent (efficient) vs. incandescent (not) Making Electricity –Renewable – better for environment Wind, hydro, sun, … –Non-renewable – larger negative impact Fossil Fuels (gas, coal, oil) Nuclear (problem of waste disposal)

SPACE

Frames of reference Geocentric (old ideas) –Earth centered model Earth in middle, then moon around, then sun, then stars, etc… Heliocentric –Sun centered model –Earth goes around sun and moon goes around earth Size –Earth – Sun – solar system – galaxy (milky way) - universe

Space Co-ordinates Used to show a location of a space object Azimuth –360 o horizontal, clockwise from due north Altitude –90 o vertical above horizon N E S W

Telescopes Refracting –Lenses –Very clear pictures Reflecting –Mirrors Radio –Radio waves – big picture – wide view –Can be used day or night, cloudy etc…

Spectra Light patterns that show what a star is made of 3 types –Bright line & continuous & dark line Spectral analysis –Spectroscope lets you determine the composition of a star – identifying gasses (elements) Doppler effect –Blue shift – moving towards you –Red shift – moving away from you

Distance in space Triangulation – to measure distance to an object –Require baseline length and 2 angles –The longer the base line the more accurate the measurement Astronomical Unit (AU) –Distance to sun from earth Light Year –Distance light travels in a year (63240 AU)

Space Travel Rockets / Shuttles –Carry payloads to space –Fuel (chemical propulsion) –Launches (lots of fuel to escape gravity) Easier to launch from ISS (less fuel needed) Problems –Life supports needs –Meteoroids (rocks) hitting space craft

Satellites –Space junk – debris form damaged satellites Moving at high speeds – problem of collision Also from meteoroids –Low-earth orbit Moving around the earth Close to earth – move fast –Geosynchronous Stationary to earth Far from earth – move slower

Size in Space Largest to smallest Universe – all know space Galaxy – a group of millions of stars held together by gravity Solar System – a star and its planets Stars – large or small gas balls Planets – material orbiting stars Meteoroids – rock particles in space

Solar System Planets and natural satellites around sun –Elliptical orbits Inner Planets –Mercury, Venus, Earth, Mars Outer Planets –Jupiter, Saturn, Uranus, Neptune, Pluto

Orbits Elliptical –Oval shaped Revolution time –Time to go around the sun. –Further out planets = longer time to go round sun eg. Earth = 1 year Mars = about 2 years

People in Space Biggest concern – dealing with near zero gravity (micro-gravity) –Effects on human body – bone loss, etc… Life support –Oxygen and food for long travel –Water – recycled instead of being stored Recovered from waste water (clean water & O 2 production) Time –Physical & mental constraints of living in a space craft for years

Biological Diversity

Diversity Differences –Different species Fern, cat, dog, … –Variation with-in a species Size, color, height, breeds, … Survival –Structural Adaptations Size, wings, beaks, etc. –Behavioral adaptation Learnt things, migration, etc… Biological diversity –Lots of different things living in same area –High diversity in hot, wet areas (rainforests) - closer to equator area - e.g. lots of (many) insects live here compared to mammals –Less populations means less diversity

Niche –Where it lives & what it does –Broad niche – fast to adapt to change –Narrow niche – small area Dependencies –Symbiotic relationship (symbiosis) –2 species relating to each other Competition for survival –Predator/prey relationship

Reproduction Asexual –Only one parent – fast – multiplies easily (lots of offspring) Spores (ferns) Binary fission (Bacteria & Amoebas) Budding / cuttings – animals (hydra) & plants Sexual –Greater variation and better chance of survival –2 parents (variations) – gametes zygotes Stages of reproduction Fertilization Zygote (cell division) embryo –Gametes (sex cells) have ½ the number of chromosomes compared to the zygote, embryo or adult cell fertilization

Genetic Information Variation –Continuous – many forms – e.g.. Height, mass, color… –Discrete – few forms – e.g. sex, tongue curling, … Traits –Characteristics (similar things) – Dominant or Recessive Dominant will always show – recessive can be carried but not show DD and rr parents only make Dr offspring -Inherited traits – skin colour, hair colour, eye colour -Non-inherited traits – scars, behaviours & abilities Mutations – changes in DNA –Good and bad

Cell Division Mitosis –Formation of adult cells from other adult cells Meiosis –Formation of reproductive (sex) cells (gametes)

DNA Genetic fingerprint – inherited material Chromosomes – strands of DNA –Carry the traits (genes) Genes – section of chromosomes –Segment of DNA –coding for a protein or trait (characteristic) Genetic Engineering –Inserting genes into chromosomes –Splicing DNA together

Selection Natural Selection –Survival of best suited for environment Artificial Selection (biotechnology) –Best for human use – food, wheat, etc… –Selective breeding – desired traits Dairy producers – lots of milk

Human Impacts Negative –Habitat loss – human land usage Extirpation (gone from a smaller area) Extinction (gone from earth) Positive –Preserving biodiversity (Genetic Biodiversity) Natural Areas/Parks Zoos for animal biodiversity Seed banks – to preserve genetic diversity International treaties – stopping illegal trade

The EXAM

Provincial Achievement EXAM 55 questions –50 multiple choice -- 5 numeric response 1 hour and 45 minutes –Lots of time (DO NOT RUSH – READ CAREFULLY) 3 answer sheets –1 provincial & 2 school (m/c & NR) Bring –Pencils, eraser, calculator, and book to read after Write on your test book –This is your scrap paper (use it) Tear-out sheet at back of test with formulas and periodic table

Textbooks If you have one at home or anywhere, PLEASE bring it back on TEST day

Next Few Days writing 9 –practice test questions for science & Questions

Practice Exams There are 2 past PAT EXAMS on D2L –They are found in the content area of the Science D2L. Using your Key or SNAP study guides have good practice questions These study notes will be posted on D2L if you missed any of them. (content area)

THANK-YOU This has been a fun year in science and you all have done very well. Good luck with your final It’s all up to you now – year review notes !!!! The KEY Unit review notes Your notes Textbook Have a great future! I miss you already!

You are part of 3.8 billion years of evolutionary success. – You got this!!