year in review. lab safety safety equipment –e.g.. fire extinguisher, first aid, eye wash, etc...
TRANSCRIPT
Year in Review
Lab safety
• Safety equipment– E.g.. Fire extinguisher, first aid, eye wash, etc
• Safety symbols – WHMIS
• Smart working– No fooling around, common sense
• Following procedure– Do what you are asked to. etc
Labs
• Variables– Manipulated – what you change– Responding – what happens due to
manipulated variable changing– Controlled – what you have to keep the same
• Conclusion– Answers to the problem of lab - statement
Environmental Chemistry
Chemicals in the environment
• Nutrients – required for all animal growth– Organic – Carbohydrates, proteins, lipids
(Fats)– Inorganic – Minerals
• Fertilizers – required for plant growth– Nitrogen – leaf growth– Phosphorus – roots and fruit– Potassium – flowers and tolerance to change
• Problems in the Environment and Food– Pesticides, herbicides, insecticides, fungicides
• E.g. DDT – effect more than what they are intended to do
– Bioaccumulation• Food chain• Increased concentrations to top of food chain• E.g. Bugs – fish – birds – top predator
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
• 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– e.g. Liming (base) of acidic lakes – to make neutral – pH 7
Air Pollution
• Acid rain– pH less than 5.6
– Caused by SO2, NO2, CO2
– Moved around the world by global winds• Global problem from industries
• Particulates and gases– Removed from exhaust by scrubbers and
filters
Pollutants
• Anything not naturally occurring in the environment
• Toxicity– Acute vs. Chronic
• Short term or long term to effect something
• LD50 – Lethal dose 50%– How much will be the Lethal to 50% of a population
• PPM – parts per million– 1/1 000 000 or 1mL/1 000 000mL
Water Pollutants• Point source
– Coming from one definable location– close to release point– e.g. waste from factory into river
• Non point source– Location of origin not known– distant to release point– e.g. air pollution from cars (driving all over the place)
• Indicator tests– DO2 – dissolved oxygen– Phosphates – enhances growth– Nitrates – growth– Biological indicators
• Landfills– Sanitary vs. secure– Leaching of chemicals
• Local problems (close to site very concentrated)• Further away it gets diluted
• 4R’s– Reduce, Reuse, Recycle, Recover
• Environmental issues– Energy Conservation– Seen from many point of views (perspectives)
• Environmental• Political• Economic• Social
Chemistry
Chemicals
• Safety– Chemical symbols– WHMIS
• Workplace hazardous
materials information
system• Symbols
• Matter– Solid (s), Liquid (l), Gas (g)– Mixtures vs. pure substances
• Mixtures – mechanical & solutions• Pure substances – elements & compounds
Changes
• Physical Change– Size– Shape– State Change (s to l to g)
• Chemical change– New substance– Gas released (smell)– Temp change– Color change
Chemical structure
• Atom– Electrons (-) & nucleus– nucleus contains protons (+), neutrons (no charge)
• Elements– Symbols – e.g. C, O, H, Na, Cl …– Periodic Table – information about elements
• Atomic # equals # of electrons or # of protons• Mass – atomic # equals # of neutrons
• Compounds– 2 or more different elements combined
• E.g. H2O, CO2, NaCl, C6H12O6, CH4, H2O2, NH3
Chemical formulas• Compound makeup
– H2O – 2 Hydrogen atoms & 1 oxygen atom– CO2 – 1 carbon atom & 2 oxygen atoms
• Molecular compounds– Share electrons – e.g. CO– made up of non metals
• Ionic Compounds– Transfer electrons from one atom to another– Ions (+ or -)– made of a metal and a non metal– Good conductivity in water due to ions
• Electrons are loose in the Molecule
– E.g. NaCl – table salt – in water good conductor
Chemical Reactions
• Chemical equations– Reactants Products– H2(g) + O2(g) H2O(l)– (g) gas, (l) liquid, (s) solid,
(aq) aqueous - in solution
• Endothermic– Feels cold – energy gained in reaction
• Exothermic– Feels Hot – energy released in reaction
Corrosion• Oxidation of metals
– A reaction where Oxygen is used up
• E.g. Rust on iron (exothermic)
• Fast reaction– Hot and wet
environments
• Slow Reaction– Dry and cold
environments
• Combustion• involves combining a
substance with oxygen
• highly exothermic (produces heat)
• requires heat, oxygen and fuel
• e.g. burning wood• e.g. gas combustion
in a car
Reaction Rate• How fast a reaction will take place• Four factors affecting Reaction Rate
– Surface area• ↑ Surface Area of reactants ↑ Reaction Rate
– Concentration• ↑ Concentration or reactants ↑ Reaction Rate
– Temperature• ↑ Temp of reactants ↑ Reaction Rate
– Stirring (agitation)• ↑ Stirring of reactants ↑ Reaction Rate
– Catalyst – speeds up reaction, is not used up
Electricity
Charges
• Electric Charges – caused by the movement of electrons (-)– Positive– Negative– Neutral
• 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
• Superconductors– Flow of electrons with no loss of energy
• Resistors– Slows the flow of electrons
Circuits
• Pathway for electricity• Electric Circuits
– Large current & voltage, long distances• Controlled by switches
– Circuit diagrams• Symbols• Working or not???
• Micro-electronic circuits – (circuit boards)– Small current and voltage, short distance
• Controlled by transistors
Circuits
• Parallel– Each load has its own path for elec.– Lights stay bright with additional ones added
• Series– Loads share paths for elec.– Lights get dimmer with additional ones added
Measuring Electricity
• Current (l)– 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)
• Ohm’s Law R = V / l
Making / Using Electricity
• Battery – Chemical to Electrical– 2 different metals (electrodes) & electrolyte solution
• Thermocouple – Heat to Elec.– 2 different metals attached at one end
• Resistor – Elec. to heat• Motor – elec. to mechanical• Generator – mechanical to elec.• Light bulb – electricity to light• Solar cell – light to elec.• Speaker – elec. to sound • Crystal – sound to elec
Electric Motors
• 4 main parts of a DC motor– Brushes
• Connect elec. to motor and commutator
• Commutator– Changes direction of current every half turn
• Armature– Elec. Magnets that spin
• Permanent magnets– Must be opposite poles
Electric Safety
• Prevent overheating, shock, and appliance damage– Fuses
• One time use, wire burns out
• Circuit breakers– Automatic switch – turns off with too much
current– If loads add up to more Amps than breaker
rated for, it cuts off
Electricity Calculations
• EfficiencyEfficiency = (Output (useful) E / Input (total) E) x 100%
• Power (P)Power = Energy / time
• CostCost = kWh (usage) x $/kWh
Electricity & Environment
• Efficiency and conservation– Using energy efficient appliances
• E.G. Florescent (efficient) vs. incandescent (not)
• Making Electricity– Renewable – good for environment
• Wind, hydro, sun, tidal, ….
– Non-renewable – negative impact• Gas, coal, oil, nuclear, ….• Alberta is primarily non-renewable
SPACE
Frames of reference
• Geocentric– Earth centered model
• Heliocentric– Sun centered model
• 1 day – earth’s rotation
• 1 year – rotation around sun
Space Co-ordinates
• Used to show a location of a space object
• Azimuth– 360° for north– Compass bearing used to measure
• Altitude– Height above horizon– Astrolabe used to measure
Telescopes
• Refracting– Lenses (objective & eyepiece)
• Reflecting– Mirror (main objective, secondary, eyepiece, aperture
opening)
• Radio– Radio waves – big picture – connecting telescopes
• Best images– From space – Hubble telescope – no distortion
(adaptive optics)
Spectra
• Light patterns that show what a star is made of• 3 types
– Bright line & continuous & dark line
• Spectral analysis (reading the finger prints of stars)– Combining dark line spectra of 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• Parallax
– Movement of distant stars relative to a close one• Astronomical unit (AU)
– Distance to sun from earth( about 1 500 000 km)• Light Year
– Distance light travels in a year (63240 AU) or (about 9 500 000 000 000 km)
Space Travel
• Rockets– Carry payloads to space– Fuel vs. lift (mass)
• Satellites– Low-earth orbit
• Moving around the earth• E.g. GPS, cameras, remote sensing
– Geosynchronous • Stationary to earth• E.g. communication (TV & Radio)
Solar System
• Planets and natural satellites around sun– Elliptical orbits
• Inner planets– Mercury, Venus, Earth, Mars
• Small, terrestrial, few moons
• Outer Planets– Jupiter, Saturn, Uranus, Neptune, Pluto
• Large, Gaseous, lots of moons
• Natural satellites: (reflecting sun’s light)– Moon – a natural satellite to earth– Planets – natural satellites to sun
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
• Time– Physical & mental constraints of living in a
space craft for years
Biological Diversity
Diversity
• Differences– Different species
• cat, dog, rose, amoeba– Kingdoms – Animal, Plant, fungi, virus,
• How to tell them apart– Variation with in a species
• Size, color, height, breeds, …
• Survival– Structural Adaptations
• Size, wings, beaks, etc…– Behavioral adaptation
• Learnt things, migration, etc…
• Niche– Where it lives (ecosystem – Habitat) & what it does in
relation to other organisms
• Dependencies– Symbiotic relationship (symbiosis)
• Mutualism: Benefit to both species• Commensalism: Benefit to one species, no harm to the other• Parasitism: Benefit to one species, harm to the other
• Competition for survival– Predator/prey relationship
• Both follow any population changes (both up and down at the same period)
– Competition for same food
Reproduction• Asexual
– Only one parent – fast – multiplies easily• Spores (ferns)• Binary fission (bacteria & Amoebas)• Budding – animals (hydra) & plants
• Sexual– 2 parents (variations) – gametes zygotes
• Animals – sperm & egg– External vs. internal fertilization
• Plants – pollen & ovum– Cones vs. flowers – contain both reproductive parts
– Gametes have ½ the number of chromosomes compared to the zygote
Genetic Information
• Variation– Continuous – many forms – e.g.. Height, mass,
color…– Discrete – few forms – e.g. sex, thumb, earlobe, …
• Traits– Characteristics (similar things) – Dominant or
Recessive– Heritable vs. Non-heritable
• Mutations – changes in DNA– Good and bad– Adaptations – e.g.. Parasites (diseases) adapting to
withstand medications
DNA
• DNA
• Chromosomes – strands of DNA
• Genes – section of chromosomes– Coding for a protein or trait
• Genetic Engineering– Making a new hybrid species for other DNA– Inserting genes into chromosomes
Production of Cells in Multi-cellular Organisms
Mitosis• responsible for growth &
repair … in every cell of the body (somatic cells)
• starts with duplicating of chromosomes
• then cell splits… forming 2 daughter cells – genetically identical to parent
Meiosis• responsible for producing
sex cells – gametes• cells go through mitosis• then a 2nd cell division
happens to daughter cells• producing a total of 4
cells (gametes), each with ½ number of original chromosomes
Selection
• Natural Selection– Survival of best suited for environment– Adaptations in genetics assist to survive– Darwin – Finch birds – many different beaks
for specific niche and survival
• Artificial Selection– Best for human use– Selective breeding
Human Impacts
• Negative– Habitat loss – human land usage
• Extirpation (gone from a smaller area) vs. extinction (gone from earth)
• Positive– Preserving biodiversity (Genetic Biodiversity)
• Natural – establishing preserves• Zoos for animal biodiversity• Seed banks for plant Biodiversity
Provincial Achievement Exam
PAT
• 55 questions– 50 multiple choice and 5 numeric response– take your time… read questions carefully
• 1 hour and 30 minutes – PLUS extra 30 min if needed
– DO NOT RUSH
• 2 Answer sheets• Bring
– Pencils, sharpener eraser, calculator, book to read after
• Write on your test book– This is your scrap paper (use it)