Normal Size Small Size show me how
Grade 9 Science Exam
Grade 9 Science Review
|What is matter?
|Matter is anything that takes up space and has mass.
|What is chemistry?
|Chemistry is the study of matter.
|What is a physical change?
|Physical change is when the appearance of a substance changes, but chemical structure stays the same. Reversible
|What is a chemical change?
|New substance is formed with new chemical structure. Irreversible
|5 Indications of a chemical change has occurred
|1. New color 2. New gas is formed(possibly new odor) 3. Light is produced 4. Heat is lost or gained 5. Precipitate forms (2 liquids form a solid)
|What is a physical property?
|a characteristic of a substance that may help you identify it.
|What is a chemical property?
|The behavior of a substance as it becomes a new substances.
|what is the particle theory?
|1. all matter is made of particles 2. pure substance have their own particles 3. particles are always moving 4. there are attractive forces between particles.
|What is a pure substance?
|Contains only 1 kind of particle.
|What is a element?
|a pure substance that can not be broken down into simpler substances.
|What is a compound?
|a pure substance that contains 2 or more different elements in a fixed proportion.
|What are molecules ?
|when 2 or more atoms join together.
|What are mixtures?
|contains 2 or more pure substances or 2 different types of particles.
|What is a homogeneous mixture?
|A substance that is composed of similar elements(uniform nature)
|What is a heterogeneous mixture?
|2 or more substances are visible.
|What are electrons?
|Negative charged subatomic particle. located around nucleus. 0 units
|What are Protons?
|positive charged subatomic particle. Located in the nucleus. 1 unit
|What are neutrons?
|Neutral subatomic particles. Located around the nucleus. 1 unit
|How many electrons are allowed as a maximum on each valence shell?
|2 8 8 2
|What is the octet rule?
|all atoms want to have a full valence shell.(8)
|2 types of bonds?
|Covalent & Ionic
|What are ionic bonds?
|nonmetal + metal
|What are covalent bonds?
|What is electricity?
|is based on electron flow
|What is electrostatics?
|the study of electricity
|What is the electrostatic series?
|a list of substances describing their relative attraction for electrons
|What are ions?
|Charged atom which have gained or lost electrons.
|What are the 2 ways of charging an object?
|Charge by contact charge by induction
|What is charging by induction?
|near the object
|What is a conductor?
|Materials that allows electrons to flow easily
|What is an insulator?
|materials that hold electrons tightly and do not transfer electricity well.
|What is grounding?
|ground wire is connected to the earth to dilute the earth
|What are 3 uses of static electricity?
|1. Pollution & dust control 2. coating surfaces 3. Copying printed material
|What are the four parts of a electric circuit?
|1. Switch 2. source 3. conducting wire 4. Electrical load
|What is the law of repulsion?
|it is the law which like objects are repelled and opposites are attracted.
|What is electric current?
|flow or movement of electric charge from one place to another.
|What is a source?
|source of electrical energy
|what is an electrical conductor?
|wire that provide a controlled path for the flow of electrical current
|What is an electrical load?
|device that converts electrical energy into useful energy
|What is CURRENT?
|rate at which a number of electrons move past a given point through a circuit in 1 second
|What is current measured in?
|What is an ammeter?
|measures electrical current
|What is the formula for current?
|I = Q/T
|charge moving past a point(coulomb/c)
|What is an open switch?
|no current flows
|What is a closed switch?
|What is voltage?
|Electric Potential" potential given to each e- as it leaves a source
|What is a voltmeter?
|it measures difference in potential energy on one side of the load and the other.
|What is potential difference?
|Is how much energy a load (can) uses up
|What is voltage measured in?
|Voltage (v = volts)
|Energy (j = joules)
|charge moving past a point (c = coulomb)
|What is the formula for voltage?
|V = E/Q
|What is resistance?
|a property that inhibits electrical motion, converts electrical energy to other energy forms. (more resistance it is harder to push coulombs through wire)
|What is resistance measured in?
|What is the formula for resistance?
|R = V/I
|What are the 4 factors that affect resistance(of a wire)
|1. Temperature- higher temp = greater resistance 2. Length - resistance increases with length 3. Cross sectional area - resistance decreases with a larger areas 4. Material - depends on the structure of the atoms of the metal
|What is power?
|Describes the amount of electrical energy that is converted into heat, light, sound or motion in 1 second.
|What is power measured in?
|What is the formula for power?
|P = E/T
|What is the 1st law of thermodynamics?
|energy is not created or destroyed, only changed to different forms of energy
|What is input energy?
|amount of energy used to operate a system.
|What is output energy?
|useful energy obtained from the systems
|What is waste energy?
|energy that is not helpful.
|What is the formula for efficiency?
|Energy output/Energy input X 100%
|What is a fuse?
|a metal conductor that has a much lower melting point than conducting wires. - when melted, current stops flowing. - new fuse will beeded when fuse is blown.
|What is a circuit breaker?
|- bimetallic strip bends with hot wires, releasing a hook to stop current flow - reset hook to start circuit again
|What is a hot wire?
|carry electrical energy (red/black) Large devices get 2 hot wire small devices get 1 hot wire
|What is a ground wire?
|- one wire entering the is neutral - connected to all appliances.
|What does D.C. stand for?
|What does A.C. stand for?
|What is direct current?
|Electrons travel continuously in 1 direction.
|What is alternating current?
|electrons rapidly change direction back and forth.
|What is a primary cell?
|- Disposable energy - when all material is discharged, all is used up
|What are 2 examples of a primary cell?
|Wet cells/voltaic cells Dry cells- battery is a collection of dry batteries
|What is a secondary cell?
|a battery that can regain its charge
|What is Ecology?
|The study of how organisms interact with each others.
|What is an ecosystem?
|term used to describe the relationships among species living in a environment and the relationship among those organisms and non-living components of the environment.
|What is an ecotone?
|a transition area between 2 ecosystems/ecozones that contain species and characteristics of both ecosystems; therefore having greater biodiversity.
|What does abiotic mean?
|non-living factors or influences on organisms such as amount of sunlight, temperature and strength or direction of wind.
|what does biotic mean?
|Factors caused by the presence and roles of other living things
|What is population?
|all of the members of the same species, living in the same ecosystem or habitats
|What is a habitat?
|the conditions required for the survival of a particular species.
|What is a community?
|the collection of all populations of all the species in a ecosystem or habitat is called the community of organisms
|What is a biome?
|a collection of ecosystems that are similar or related to each other by a dominate form.
|What is a food chain
|they show the predator-prey relationship
|What is a food web
|are complex and show more inter-relationship. (they provide a more accurate picture of the ecosystem)
|What is the 2nd law of thermodynamics?
|anytime energy is converted, some of the energy is converted into an unusable form usually thermal energy that can not be converted
|What is photosynthesis?
|Sunlight is converted into sugar. (Stored chemical energy)
|What is cellular respiration?
|Sugar is converted to useful chemical energy.
|What are food pyramids?
|they show relationships between trophic levels. they are another wasy of showing food chains.
|What are the 3 types of food pyramids?
|Numbers, Biomass & energy. (least to greatest)
|What is a species?
|organisms that are similar and can mate to produce fertile offspring.
|What are the 4 ways a population can change sizes?
|Births, Deaths, Immigration, Emigration.
|What is bioaccumulation?
|pesticides that accumulate in the fatty tissue.
|What has a closed populations?
|Populations that do not have immigration & emigration.
|What are the 4 layers of soil? (top to bottom)
|Litter, topsoil, subsoil, bedrock
|What is population growth?
|Births + immigration - emigration - deaths
|What is biotic potential?
|the max # of offspring a species can produce.(depends on 4 factors)
|What are the 4 factors that affect biotic potential?
|1. Birth potential 2. Capacity for survival 3. Procreation 4. Length of reproductive life
|What is carrying capacity?
|the max # of individuals that an ecosystem can support
|What is a critical number?
|the # of organisms below which extinction will result for that species.
|What are 3 words used to describe soil?
|Acidic, neutral, basic.
|What the 3 things that determine the pH of soil?
|1. The nature of the rock from which the soil was formed. 2. the type of plants that grow in it, die & decompose. 3. The rain & snow that falls on the soil.
|What are the 3 factors that determine the type of biome and will influence the type of plants?
|1. Temperature 2. Amount and type of precipitation 3. Latitude
|What is a celestial body?
|an object in space that are visible from earth. (sun, moon stars, planets)
|What is a asterism?
|a distinctive star pattern. (the big dipper)
|What is a constellation?
|a group of stars that form a pattern.
|What is a planet?
|a celestial body that orbits a star and does not produce its own light.
|What is a supernova?
|a huge explosion constituting the death of a star.
|What is a nebula?
|a vast cloud of gas & dust, which may be the birth place of a star.
|What is a black hole?
|in space, an object having such strong gravity that nothing, not even light can escape it.
|What is a neutron star?
|a small super dense star thought to be the crushed remnant of a large star that has exploded as a supernova.
|What is a white dwarf?
|a small super hot star that is not very bright.
|What is a light year?
|the distance that a beam of light travels in a vacuum in 1 year. (9.46 trillion km)
|What is the geocentric model?
|The earth centered model; proposed by Aristotle.
|What is the heliocentric model?
|The sun centered model; proposed by copernicus.
|What is day & night caused by?
|the rotation on the earth's axis
|What does the tilt cause?
|it causes differences in temperature, hence seasons.
|what degrees is the tilt at?
|What are the 2 types of rays?
|Direct & slanting rays.
|What is an asteroid?
|Irregular shaped bodies made of carbonaceous or silicate rock. (also called minor planets)
|What is a comet?
|a celestial body made of ice & dust. (dirty snowballs)
|What is a meteor?
|a shooting star made of dust & rock.
|What is a metorite?
|A meteor that hits earth.
|What is a series circuit?
|The electrons only have 1 path to follow and the all appliances share electrical pressure.
|What is a parallel circuit?
|The electrons have more than 1 path to follow and the appliance do not share electrical pressure.
|What is a spectroscope?
|a device that splits light into a pattern of colours.
|What is luminosity?
|the amount of energy a star radiates per second.
|What are stars formed from?
|giant clouds of gas and dust known as nebulae.
|What does starlight provide?
|information about the star's brightness, color temperature, composition, mass & size.
|What is color used to find?
|Temperature (smaller wave length = hotter star)& the composition of a star.
|What are the 3 types of galaxies?
|Spiral, elliptical & irregular.
|What is a galaxy?
|stars, gas & dust held together by gravity. (they occur in clusters like stars)
|What are the 2 types of clusters that stars are found in?
|Open clusters & globular clusters.
|What is our galaxy?
|The milky way.
|What is a spiral galaxy?
|pinwheel shaped with arms of gas, dust & bright blue stars. (Which indicate the formation of new stars)
|What is type is our galaxy?
|What is an elliptical galaxy?
|a football shaped of mostly old stars with little gas & dust.
|What is a irregular galaxy?
|young & old stars in gas and dust. Usually small and less common.
|What are the 3 ways of transferring electrical charge?
|By friction, by contact, and by induction.
|What are the 3 things involved in the nitrogen cycle?
|Decomposer, bacteria and animals.
|What is nitrification?
|The process in which atmosphere nitrogen converting to nitrates.
|What is dentification?
|Process performed by some soil bacteria in which nitrates are converted to nitrates and then to nitrogen gas.
|What are the 2 processes involved in the carbon cycle?
|Photosynthesis and cell respiration.
|What are tides caused by?
|The gravitational pull of the moon.
|During a lunar eclipse what is in the centre?
|During a solar eclipse what is in the centre?
|When would the sun be above the horizon for the most hours?
|June 22 the Equinox.
|In which season can we see the big dipper?
|What is the hubble?
|How do you figure out the number of neutrons?
|Atomic mass - atomic number = number of neutrons
|What is an isotope?
|An atom with different number of neutron and different atomic mass, but is the same element.
|What are the 4 main abiotic factors of ecosystems?
|Light, temperature, wind and moisture.
|What are the 3 light factors in an ecosystems?
|Intensity, duration and quality.
|What is an organic substance?
|A substance always containing atoms of carbon and hydrogen.
|What is the definition of extirpated?
|any species that no longer exists in a certain part a country.