Science Exam

CHEMISTRY

Classify matter:

Pure substances -

Elements: can't be broken down (P.T)
Compounds: made from 2 or more elements

Mixtures -

Heterogeneous;

Mechanical: can visually see the different matters ex. salad

Suspension: Cloudy mixture where tiny particle of one substance is held in another Ex. Hot chocolate

Homogeneous;
Solutions: cannot see the different substances ex. apple juice

Colloid: tiny particless are scattered through another Ex. Marshmallow, Air in solid

Chemical changes:

Rusting, combustion (anything where the original substance is changed into other substances that have different properties)

Clues- New colour, new odour, bubbles of gas, heat/light, precipitate (solid->liquid)

Qualitative and quantitative physical properties:

Qualitative - Gather from senses (words) Quantitative- measured with numbers

Ex. Colour, optical clarity, odour, texture, state, malleability, ductility, melting/boiling point, solubility, viscosity, lustre, (conductivity), hardness, density

Chemical properties:
Combustibility, Flammability, Light sensitivity, Reaction with an acid

Density problems (ex):

Calculate the density of a metal sample that is 18 cm long, 9.21 cm wide, and 4.45 cm high, that has a mass of 14.25 kg. What is the density of the metal?

D = m/v = 0.01425g/(18×9.21×4.45) = 19.316 SIG FIGS = 19.3g/cm3

Sig digs:

Multiply = sig figs

Add = decimals

Define and give examples of elements, compounds and isotopes:

Elements - Mercury, Iron, Sodium

Compounds - H2O, NaCl, CO2

Isotopes - Same element but different neutrons, so average mass is used

Name the elements in a formula (ex):

NaOH = Sodium, Oxygen, Hydrogen

NH4Cl = Nitrogen, 4 Hydrogens, Chlorine

Count the atoms in a chemical formula (ex):

Cl2 = 2 atoms of Chlorine bonded together (HOFBrINCl)

Discuss the atomic models of Dalton, Thomson, Rutherford, and Bohr:

Dalton - Billiard ball (tiny particles, identical, different elements = different atoms, atoms cannot be created/destroyed)

Thomson - Plum pudding (Positive atom with negative particles)

Rutherford - Nuclear (Proton in center called nucleus, around is negatively charged electrons)
Bohr - Planetary (Proton center orbited by electrons)

Determine: # of protons, neutrons and electrons:

Isotopes - Protons & Electrons = atomic number Neutrons = Atomic mass - Atomic number (protons)

Ions - Protons = same as isotope Electrons = filled valence shell so net charge can be positive or negative Neutrons = Atomic mass - Atomic number (protons)

Determine atomic number, atomic mass, standard atomic notation:

AN - Number of protons (& electrons)

AM - mass of an atom consisting of the nucleus, ADD # OF PROTONS AND # OF NEUTRONS = amu or u,

SAN - Mass number (bigger) on top left (round mass), atomic number on bottom left, Symbol in center

Draw Bohr-Rutherford diagrams (atom, ion, ionic compounds, molecular compounds) (ex):?

DONE

Show the formation of ionic compounds using Lewis diagrams (electron-dot diagrams) (ex):

[F]1- [MG]2+ [F]1-

Magnesium fluoride

MgF2

Draw Lewis structures (covalent compounds) (ex):

H — O — H

Dihydrogen Oxide

H2O

Distinguish between metals and non-metals:

Metals- solid, lustre, conductive, malleable, ductile

Non-metals- gases, powdery solids, opposite of metals

Determine the group and period of an element & what they tell us about an atom’s structure:

Group - vertical ↓ (Increase in valence electrons)

Period - horizontal → (Increase in electron shells)

Identify alkali metals, alkaline earth metals, halogens, and noble gases:

Alkali metals - group 1, 1 electron in valence, most reactive metals, shiny, soluble

Alkaline earth metals- group 2, 2 electrons in valence, shiny, silver, insoluble

Transition metals- middle

Halogens- group 17, 7 electrons in valence, most reactive non-metal, poisonous, react with Alkali

Noble gases- group 18, 8 electrons in valence, non-reactive, do not form compound

Explain how negative ions (anions) and positive ions (cations) form:

Cations (+) - When the Ion loses electrons, it becomes positive

Anions (-) - When the Ion gains electrons, it becomes negative

Name ionic compounds (binary, multivalent and polyatomic) and write formula:

Binary - Names of compounds

Multivalent - Differing roman numerals (transitions)

Polyatomic - Has Polyatomic ions

Write word equations and balance chemical equations (ex):

Fe2​O3 ​+ H2 ​ → Fe + H2​O = Fe2​O3 ​+ 3H2 ​→ 2Fe + 3H2​O

Iron (III) Oxide + Hydrogen (g) → Iron + Air

BIOLOGY

Biotic & Abiotic factors:

B - Living components: organisms, remains, products, wastes. Ex: fish, dead fish, offspring, poo

A - Non-living components: physical & chemical. Ex: wind, water, temp, minerals, air

Differentiate between limiting factor, tolerance range and carrying capacity:

Limiting factor: Restricts the size of the population (B- availability of food or A- access to water)

Tolerance range: The survival range of each species

Carrying capacity: Species size limit of ecosystem

• Population increases, need for resources increase

• More susceptible to predators and diseases

Discuss species interactions:

Mutualism - Both benefit

Commensalism - 1 benefits, 1 neutral

Ammensalism - 1 harmed, 1 neutral

Predation - 1 benefits, 1 harmed (Predatory, whatevers not parasites)

Parasitism - 1 benefits, 1 harmed (Insects, parasites)

Explain why biodiversity is important in ecosystems:

So that the food web can flourish even when one species dies out

Explain predator/prey relationships:

Predator hunts prey. Normally to get energy (10% fanum tax for each predator)

Analyze a food chain and/or food web and the flow of energy (ex):

Arrow pointed to predator. 10% fanum tax for each predator. Measured in Joules.

Draw food chains, food webs and ecological pyramids (ex):

______ → ______ → ______ → ______ = Food Chain

______ → ______ → ______ ^ = Food Web

Pyramids - Energy = 🔼 Numbers = 🔽 Biomass = 🔼

Explain the carbon cycle (ex):

Carbon is cycled through the atmospheres

Plants need CO2

When fossil fuels are burnt, it sends more CO2

Explain the nitrogen cycle (ex):

Nitrogen fixation = N2 → NH3

Explain why photosynthesis and cellular respiration are complementary processes - write the word and chemical equations for photosynthesis and cellular respiration

Photosynthesis happens in the morning with sunlight to create sugars, using those sugars, Cellular respiration happens.

Photosynthesis - (Light energy)

Carbon Dioxide + Water → Glucose Sugar + Oxygen

CO2 + H2O → C6H12O6 + O2

Cellular Respiration -

Glucose Sugar + Oxygen → Carbon Dioxide + Water + (Useable) Energy

C6H12O6 + O2. → CO2 + H2O + E

Explain the importance of decomposers in an ecosystem:

Without decomposers, other organisms int he food chain wouldnt be able to recycle the nutrients of the dead back into the soil.

Distinguish between the terms: herbivore, carnivore, omnivore, producer, and niche:

Herbivore - Only eats plants

Carnivore - Only eats animals

Omnivore - Eats both plants and animals

Producer - Organisms that photosynthesize

Niche - Function if a species in ecosystem (species feeds on, what eats it, how it behaves)

Discuss the impact of invasive species on native species:

Eat things they aren’t supposed to and

Explain the impact of pesticides and bioamplification:

Pesticides can either kill a specific pest or kill a multitude

Bioamplification - when one organism is affected by toxins, the deeper into the food chain, the more the pesticide accumulates

Explain why DDT is banned in North America:
Operation cat drop

DDT = Broad-spectrum

• Killed mosquitoes

• Killed wasps that ate thatch-eating caterpillars (Thatch houses destroyed)

• Killed cockroaches → damaged lizards systems → cats poisoned and died ← rat population increased → plague increased

Discuss the benefits of modern pesticides:

Making of expensive narrow-spectrum insecticides

Distinguish between oligotrophic and eutrophic lakes:

Oligotrophic - Lake low in nutrients (slow growth, low population density)

Eutrophic - Lake high in nutrients (dense plant population, low oxygen)

PHYSICS

Explain the Law of Electric Charges:

Like charges repel each other; unlike charges attract

Explain charging by friction, conduction, & induction:

Friction - Electrons transfer from 1 to another when rubbed (electrostatic) then stick together cuz of the law ^

Conduction - In contact, electrons move. [charged → neutral or charged → charged (Always goes from most to least charged)]

Induction -

Temporary loss of electrons = when charged is brought near neutral, electrons shift, uneven distribution)

Permanent loss of electrons = when charged is brought near neutral, electrons shift, you can use grounding to transfer/take electrons

Ue the Electrostatic Series – to determine which materials tend to gain or lose electrons (ex):

SEE IMAGE

Explain how “grounding” works and why it is necessary:

Connecting a conducting object to the Earths surface; transferring electrons

Protection form electric shocks

Distinguish between conductors and insulators:

Conductors - can transfer electrons (Good, fair) Ex. Mostly metals

Insulators - cannot transfer electrons

Explain why metals are good conductors:

Because the electrons are free to move in a network of the metal atom.

Explain what insulators do with charges:

Charge cannot flow, non-metals

Differentiate between static and current electricity:

Static - Stationary, stays in one place

Current - Flows

Explain the effects of humidity on static electricity:

If its too humid, it makes the air more conductive so it absorbs and evely distributes excess charges so friction is harder to acheive

Draw and label circuit diagrams (ex):

?

Use circuit symbols (ex):

Cells, Resistor, Fuse, Wire, Ground, Lamp, Switch, Ohmmeter, Ammeter, Voltmeter, Motor

Explain relationships and calculate – USING GRASS – current, potential difference (voltage), resistance, power, percent efficiency, cost of electricity and equivalent resistance

Power - P = IV OR P = E/T

Current - I = P/V OR I = V/R

Voltage - V = P/I OR V = IR

Resistance - R = V/I

% Eff = (Energy Out / Energy In) * 100% Eout is always smaller, Ein is bigger

Cost = P (kW) x t (H) x cost of electricity [¢] (rate) (kWH)

APPLY SIGDIGS

- use the symbols and units for current, potential difference, resistance, power and efficiency properly

I, V, R, P, %Eff

Discuss factors that affect resistance

Type of material - Better conductor (least resistant) = Fewer collisions

Cross-sectional Area - Larger diameter = less collisions and opposition, more room

Length - Shorter = less resistance

Temperature - Colder = less collisions and resistance

Describe how to measure current and potential difference in a circuit

Ammeter - Current (Series)

Voltmeter - Voltage (Parallel)

Ohmmeter - Resistance (Parallel)

Analyze series and parallel circuits to determine voltage, current and/or resistance

Kirchoffs Laws

Series → (I t = I1 = I2 ….) (V t = V1 + V2 ….) (R t = R1 + R2 ….)

Parallel → (I t = I1 + I2 ….) (V t = V1 = V2 ….) (1/R parallel = 1/R1 + 1/R2 ….)

Name conventional and alternate ways to generate electrical energy

Nuclear, wind, solar, hydro, biomass, geothermal power plants

Distinguish between renewable and non-renewable energy resources

Renewable - Naturally replenished without human interference (Ex. Solar, Hydro, Wind energy)

Non-renewable - Finite; Will eventually deplete without human interference (Ex. Fossil fuels, nuclear energy)

ASTRONOMY

Describe inner/outer planets; gas vs. terrestrial planets:

MeVEMa | JSUN

Terrestrial - Mostly solid, Made of rocks and/or metals

Gas Giants - Larger, made of gases

Differentiate between solar and lunar eclipses:

Solar - Moon is between Sun and Earth

Lunar - Earth is between Sun and Moon

Explain why Pluto is no longer classified as a planet

3 qualifications:

1. Orbits around the Sun ✅

2. Has a nearly round shape ✅

3. Has its own orbital path ❌

Define units of AU and ly and calculate distances (Apply sig digs & Scientific Notation):

AU - Astronomical Units

• Measuring distances within the Solar System

• 1 AU = distance from the Sun to Earth

• 1.5 × 10^8 km = 1 AU MEMORIZE THIS

ly - Light Years

• Measuring distances outside the Solar System

• 9.46 × 10^12 km - 1 ly

Discuss properties of stars – colour and temperature:

Blue → White → Yellow → Orange → Red

Hottest —> Coldest

Composition of stars (ex):

Core, Radiative Zone, Convective Zone

Photosphere, Chromosphere, Corona

Outline life cycle of stars (small/medium, large, and massive) (ex):

Small/medium - Nebula, main-sequence star, red giant, planetary nebula, white dwarf, white dwarf cooling, black dwarf

Large - Nebula, main-sequence star, Supergiant, SuperNova, Neutron Star

Massive - Nebula, main-sequence star, Supergiant, SuperNova, Black Hole