Science Exam Review (Chemistry + Ecology)

CHEMISTRY:

Classification of matter chart: 

CHEMISTRY:

 Matter

Matter is anything with mass of volume.

e.g Air, water, my phone, body

2. Pure Substance

A pure substance is made of only one kind of particle. 

e.g gold (AU), Oxygen (o2), Water (H20), Carbon

dioxide (CO2)

Pure Substances and mixtures are both forms of matter but are completely different.

Pure Substances are often described as one element or multiple combined but u cannot tell there is a mixture and cannot be physically Separated, only Chemically.

However, mixtures you can see a mixture in Place and it can be separated physically.

Mixtures: a mixture is two or more substances physically mixed together, not chemically.

e.g Salad, trail mix

Comparison: 

pure Substance = Oxygen Cos, water

Mixture = Salad, trail mix

There are two different types of pure substances...

Element:

An element is a basic substance that can’t be broken down into anything simpler. 

These can be found on the periodic table

E.g Oxygen (O2), Iron (Fe), and Gold (Au)

Compound:

A compound is made when two or more elements combine together chemically.

*Element = 1 element only

Compound = 2+ elements

E.g water (h20), carbon dioxide (CO2), and Salt (NaCl)

There are two different types of mixtures… 

Heterogeneous mixture:

A mixture where you can see the different parts. They don’t blend fully. 

E.g cereal in milk, chocolate chip cookies, oil + water, trail mix, etc

Homogenous Mixture: A mixture that looks the same throughout. You can't see the different parts. E.g salt water and vinegar

There are two different types of Homogenous Mixtures.. 

Suspension: A cloudy mixture where tiny pieces are spread out but settle over time. 

E.g muddy water, orange juice pulp

Colloid: A mixture where tiny particles are spread out extremely and they don’t settle over time. 

E.g milk, fog, whipped cream

Physical/Chemical properties:

Physical property definitions:

Texture: How a Surface feels to touch

e. g Smooth, rough, gritty

Ductility: The ability of a Substance to be stretched

or drawn into Wires without breaking.

e. g "Can be made into wines"

Luster: How shiny or dull a substance appears. (How it reflects light) e.g shiny/dull

Odour: The Smell a Substance gives off. (e.g sweet, sour, burnt) e.g “it is sharp, burnt, or spicy”

State: The physical form of matter e.g solid, liquid, gas

Hardness: A material’s resistance to being scratched or dented e.g diamonds are very hard

 (e.g "Diamonds are at the top of the scale")

Melting point: The temperature at which a solid becomes a liquid.

Clarity: How clear or see through a substance is (e.g

transparent, cloudy, or opaque)

Malleability: The ability of a substance to be hammered or pressed into shapes without breaking

(e.g "can be hammered thin")

Viscosity: How easily a liquid flows. Thicker liquids have higher viscosity. (e.g honey is more viscous than water)

Solubility: How well a substand can dissolve in a liquid, like water, e.g “can it dissolve” 

Boiling Point: The temperature at which a liquid turns to gas. 

What is the difference between physical and chemical properties?

Physical Properties describe a substance without changing its identity. (e.g color, state)

solely for describing attributes of a substance by observing

Chemical properties describe how a substance reacts with other substances. (e.g flammability, reactivity, ability to rust)

Simply: Chemical properties describe how a substance changes into something new. You can only see chemical properties during a chemical reaction.

Difference:

Physical Properties:

Can be seen without changing it.

E.g Ice melts into water

Chemical properties:

Only seen after a chemical reaction (changing it)

E.g wood burns to ash and smoke

ECOLOGY:

Periodic table terms:

Period: A row on the periodic table. (Horizantal) “periods run across like a sentence” 

e.g hydrogen and Hellium

Family: A column on the periodic table (also called a group) (Go up and down/vertical)

Elements in a family have similar properties.

E.g Group 1: Alkali Metals (Lithium, sodium, etc)

Non-Metal: Elements that are usually dull, brittle, and are poor conductors of heat and electricity. 

Metalloid: Elements that have properties of both metals and non-metals. (e.g can be shiny but brittle)

Metal: Elements that are shiny, good conductors, and can be shaped (malleable/ductile) 

Alkali Metals: Elements in Group 1. Very reactive, especially with water. (e.g sodium, potassium)

Alkali Earth Metals: Elements in Group 2. Not as reactive as alkali earth metals but still reactive.

Halogen: Elements in Group 17. Very reactive non-metals. (e.g chlorine, fluorine).

Nobel Gas: Elements in Group 18. Very stable and nonreactive gases. (e.g helium, neon)

ECOLOGY:

Abiotic Factors: Non living parts of an environment. (water, sunlight, temperature)

Biotic Factors: Living parts of an environment. (plants, animals, fungi)

Bioaccumulation: When harmful substances build up in one organism over time. 

Biomagnification: When those substances increase as they move up the food chain. 

Biosphere: All areas on earth (where life exists)

Equilibrium: a balanced ecosystem, where everything stays stable. 

Extinction: Where a species completely disappears. 

Food Web: A bunch of food chains connected together. 

Decomposer: Breaks down dead things and recycles nutrients (bacteria, fungi)

Predator: Hunts and eats other animals.

Prey: The animal that gets eaten by the predator.

Omnivore: Eats both plants and animals (like humans) 

Lithosphere: Earth’s solid outer layer (the ground/crust)

Acid Rain: Rain made acidic by pollution, which harms our soil, water and planet.

Trophic level: the step/level an organism is at in a food chain. (e.g producer, primary consumer, etc)

Respiration: the process of using oxygen to turn food into energy. 

Carnivore: (lions) eat only meat. 

Atmosphere: the layer of gases around the earth. (oxygen, carbon dioxide, etc)

Aquatic ecosystem: water based environment (lakes, rivers, oceans) 

Biodiversity: the variety of living things in an ecosystem

Community: all living things in an area that interact 

Herbivore: Eats only plants.

Hydrosphere: all water on earth

Food chain: A straight line showing who eats who. 

Diversity: Variety of different forms in life. 

Forestry/deforestation: managing or cutting down forests. Deforestation is removing trees. 

Consumer: Organism that eats other organisms for energy.

Invasive species: A species not native to an area that harms the local ecosystem.

Niche: a specific role or job in an ecosystem.

Pesticides: Chemicals used to kill pests but can harm ecosystems. 

Nutrient cycles:  How water and carbon move through the earth and living things. 

(water, carbon).

Photosynthesis: plants make food using sunlight, water and carbon dioxide. Sunlight + water + CO2 = glucose + O2 (Word equation) 

Biome: A large ecosystem with a certain climate and organisms (like a desert, rainforest)

Producer: makes its own food

Species: a group of similar organisms that can reproduce

Ecosystem: all the living and non-living parts of an area working together. 

Population: a group of the same species living in one area. 

Pyramids: shows energy, numbers, or biomass at each trophic level.

Sustainability: Meeting our needs without harming the environment or future generations. 

Soil:

Layers

Topsoil - the top layer with lots of nutrients. Plants grow here. 

Subsoil - under the topsoil. Has less nutrients, more rocks and clay. 

Bedrock - the bottom layer, made of soil rock.

Water cycle questions:

Define Transpiration, evaporation, condensation, and precipitation, when does each occur? 

Evaporation: 

Water changes from liquid to gas (water vapour) and goes into the air. 

Happens: Oceans, lakes, rivers, puddles. 

Transpiration: 

Plants release water vapour from their leaves into the air. 

Happens: on leaves of plants and trees

Condensation: Water vapour cools down and changes back into liquid, forming clouds. 

Happens: in the sky

Precipitation: water falls from clouds as rain, snow, or hail.

Happens: from clouds to the ground.

Water’s impact on humans?

• Drink it to stay alive

• Uses it for farming, cleaning, cooking, etc

• Supports healthy ecosystems

Humans impact on water:

• Pollution from factories, farming (pesticides) and garbage can create dirty water

• Water waste

Carbon Cycle Questions:

4 reservoirs in the biosphere…

1. Atmosphere

2. Living things (Plant + animals) 

3. Fossil fuels and soil - carbon stored underground

4. Oceans - carbon dissolved in water and sea creatures

Where does carbon dioxide in the atmosphere come from?

• Breathing (respiration) from people and animals

• Burning fossil fuels (cars, factories) 

Why is Carbon important? 

• Main part of all living things

• Needed for photosynthesis

Carbon Cycle:

Carbon impact on humans vice versa:

Carbon’s effect on humans:

• Too much CO2 creating climate change

• Affects weather and health

• Rising ocean currents

Human’s affect on carbon:

• Burning fossil fuels increase CO2 in the air

• Deforestation reduces carbon removal in air

• Pollution increase carbon release

What is the source of all energy in ecosystems?

SUN. 

How much energy from the sun is used for photosynthesis by green plants? 

Only about 1% of the sun’s energy that reaches the earth is used for photosynthesis by green plants. 

What is cellular respiration? 

Cellular respiration is the process where cells break down food (like glucose) to release energy. 

*used for organisms to move, grow, and stay alive. 

Word equation: Glucose + Oxygen (O2) = Carbon Dioxide (CO2) + water + energy

Compared to photosynthesis it is flipped. 

What organisms do cellular respiration?

Almost all living things do respiration. Including.. 

• Plants

• Animals

• Fungi

• Most bacteria

They all need energy to survive, and cellular respiration gives them that energy.

What are trophic/energy levels?

Trophic levels show an organism’s place in the food chain – who eats what.

From bottom to top:

Producers

Primary consumers (herbivore)

Secondary Consumers (omnivore)

Tertiary Consumers (top carnivore)

Decomposers (breaks down dead things) (Not part of pyramid/level)

What happens to energy at each level?

Each time energy moves up a level, 90% is lost and only 10% is passed on. 

The lost energy is used for:

• Movement

• Heat

• Body Processes

This explains why top predators need to eat more and why there are so few of them.

What are food chains and what are food webs?

Food chains:

A single line of who eats who.

Food webs:

A complex map of all food webs. 

Both show how energy is moving through an ecosystem. Both use arrows to show directional energy flow. 

Identifying organisms by trophic level:

1. Producer – Grass, Algae, trees. (Plants)

2. Primary Consumer – Deer, Rabbit, Caterpillar (herbivore)

3. Secondary Consumer – Snake, Fox, Frog (omnivore)

4. Tertiary Consumer – Hawk, wolf, eagle (top carnivore)

Not in trophic level – Honorable Mention: Decomposer — earthworms, fungi, bacteria

Identify types of organisms:

Herbivore – only eats plants

Carnivore – only eats animals

Omnivore – eats plants and animals

Detritivore – Only eat dead plants + animals (earthworms, bacteria)

Decomposer – Breaks down dead stuff (fungi, bacteria, earthworms)

Building a food web. 

Go in order from producer-tertiary consumer then create many of those that may interconnect with others.

Using the periodic table to find:

Atomic # — Can find it on the top of element box

Atomic Mass – Under letters/symbol, round to whole # for use

# of protons – Found in atomic # (e.g oxygen = 8 protons)

# of electrons – found in atomic # (e.g oxygen = 8 protons)

# electrons – Rounded atomic mass - atomic # (e.g oxygen = 16 - 8 = 8 neutrons)

Standard Atomic notation –   

Symbol – e.g oxygen – O

Chemical group – Name of group (e.g alkali metals, halogens, etc)

# of valence electrons – amount of electrons on the last shell of a bohr- rutherford diagram

# of orbituals in Bohr-Rutherford Diagrams – how many orbits in a bohr rutherford diagram

Draw a bohr-rutherford diagram — ______

What pesticides are used? What types of pesticides? What does each kill?

Pesticides are used to kill pests that damage crops or carry disease.

Insecticides: Kill insects

Herbicides: Kill weeds/plants

Fungicide: kill fungicide

Bactericide: Kill bacteria

Which type of organism would be most affected by bioaccumulation/biomagnification? Why?

Top predators (like eagles/orcas) are most affected because toxins build up and magnify as they move up the food chain. 

What is DDT? What effect did it have on birds? Why?

DDT is a pesticide. It caused bird eggshells to become thin and break easily, leading to population decline. This happened because DDT interfered with calcium metabolism. 

For soil: The PH Scale tells us how acidic or basic soil is. Most plants prefer a nearly neutral PH (7). If soil is too acidic or basic it can damage the plant or make it difficult for plants to absorb nutrients. 

Soil + watercycle: helps absorb and filter water.

Human impact: pollution, deforestation, and farming all damage soil.