unit 3: science 9- environmental chemistry

Question 0

MSDS’s

Answer 0

Material safety data sheets
They are a form of label that gives information about the harmful substance to the buyer of the product
If describes precautions that should be taken when handling, using, transporting and disposing of the product
It also provides details about heal effects and how to contain or store the product

Question 1

Transport of hydrocarbons in soil

Answer 1

Contamination of soul by hydrocarbons is a problem throughout Canada
Hydrocarbons are from vehicles and in industry… They contaminate by being carried through water in the soil and spread over a wide area. They can concentrate inside the pores of the grains and not travel very far but cause a difficulty to clean up
Most hydrocarbons are toxic to plants, animals and humans

Question 2

Impact of the oil spill on people

Answer 2

Many commercial fishers could no longer sell fish
People who relied on wildlife for food ha to purchase food instead
Tourism decreased due to loss of recreation in an oil spill area
All of these effects caused a long term clean up to fully repair most of the damages done by the spill

Question 3

Factors affecting biodegration

Answer 3

Slow biodegration in the winter due to little bacteria growth
Other factors other than temp are soil moisture, pH, oxygen supply and nutrient availability
You can plant vegetation to help with the biodegration process

Question 4

Storage of hazardous chemicals

Answer 4

Leave all products in organizational containers (secured lids) and labels
In a location out of reach from children
Store in cool, dry, ventilated places
Don’t store flammable substances in glass containers or substances such as gasoline should be stored outside of the house
Store different substances on separate shelves from each other
Discard of containers that are leaking or substances that are old

Question 5

Dispersion

Answer 5

The scattering of a substance away from its source

Ex. If you spilled to much fertilizer on your lawn you could disperse it throughout the soil

Question 6

Some substances that contaminate groundwater

Answer 6

Minerals in rocks and soil: iron, calcium
Organic substances ( natural or human made): pesticides, solvents
Leached from landfill sites: heavy metals (mercury)
Leak from underground storage or pipelines: gasoline, oil
Inorganic substances( industrial processes ect.): salt, fertilizers
Improper micro-organisms: bacteria, viruses
Household chemicals: detergents, nitrates

Question 7

What dilutes or disperses a chemical quickly?

Answer 7

A fast flowing river or air mass

Dilution or dispersion combined with another clean-up process such as biodegration can be very effective

Question 8

Crude oil spills

Answer 8

Exxon Valdez is a good example…
Occurred in prince William sound and changed the beauty of the lake
The small molecules oil spilled and dispersed into the air and water
Tar balls of heavy hydro garçons were washed ashore or sank into the sediment under the water
This is a long term problem and caused a major impact on the environment

Question 9

Factors that affect the rate of groundwater

Answer 9

The soil had pores.. These pores are tiny spaces between soil grains that are sometimes tightly packed that the pores are not connected. In this case the water cannot flow through the soil as easily. If the pores are connected the soil is permeable and transports pollutants through the water more easily.

Question 10

Transport in groundwater

Answer 10

Water that soaks into soil moves first into a zone near the surface where the soil grains contain both air and water (water table) Next it will move deeper and enters a zone where all the spaces are filled with water (groundwater)
Groundwater can move sideways, up and down
The water can exonerate concentrated with substances such as lead and creates problems to drink the water and use for other purposes

Question 11

Impact of oil spills on plants and animals

Answer 11

Floating algae can be killed, invertebrates near shore could not survive due to decreased oxygen, loss of food and the toxic effect of hydrocarbons
Fish eggs and young fish were sensitive to the oil and died
Adult fish could escape by swimming away but the lost their habitat and good resources
Seabirds and mammals can become covered in oil so many of them would die as well

Question 12

Biomagnification

Answer 12

Increase in concentration of a chemical or element as it moves up the food chain
Ex. Mercury: comes from emissions from coal-fires power plants ect. The mercury falls into fresh or salt water where bacteria join it to an organic molecule that alga can absorb
After this point mercury enters the good chain through the alga and leads to insects, green plants and fish. Eventually making it onto our plates and harming humans
Mercury contaminated water is a problem in Canada’s Great Lakes

Question 13

Oil spill clean up

Answer 13

Booms am be used to clean up and obtain the spills in water

Ground spills occur too and have different procedures to clean up the spills

Question 14

Crude oil

Answer 14

A mixture of many chemicals
Contains hundreds of different molecules in all shapes and sizes
Some in crude oil contain nitrogen, oxygen and sulfur
Crude oil cannot be used right when bit comes out from the ground.. It had to be refined through a process

Question 15

Concentration of pollutants in the environment can be changed using different techniques such as..

Answer 15

Dispersion, dilution, biodegratuon, phytoremediation and photolysis

Question 16

Hazardous chemicals include

Answer 16

Household cleaners
Personal hygiene products
Pet-care products
Paint and paint products
Pesticides and fertilizers
Automotive fluids

Question 17

New product regulations

Answer 17

Intended use, physical and chemical properties and active ingredient(s)
Instructions for use, safety precautions
Heal effects, environmental effects, toxicity to humans and first aid instructions in case of poisoning

Question 18

Transportation of consumer goods

Answer 18

Should be placed in the trunk of a car where they will not fall over (secure)
Do not mix together hazardous household wastes when bringing to a collection site

Question 19

Factors of the direction and distance of airborne pollutants

Answer 19

Pollutants properties, wind speed, and the direction of prevailing winds

Question 20

Disposal if hazardous chemicals

Answer 20

Never pour wastes down the drain or into the soil
Do not throw them away in the garbage
If you do pour the substance down the drain it can enter into the sewage system it septic tanks and not be filtered, therefor they are entering into the surface water and harming the soil water, drinking water and even air

Question 21

Aerobic and anaerobic biodegration

Answer 21

Aerobic: uses oxygen in the air to grow and produce bacteria for breakdown
Anaerobic: without oxygen in the air to thrive the breakdown with bacteria

Question 22

Solid waste garbage

Answer 22

Some substances such as gasoline and oil can be recycled at a hazardous waste collection site
Take antifreeze to a recycling centre and don’t out it into the ground or drain where it will enter into your septic tank
Never place car batteries in a home garbage. They can be recycled
Take care or aresol cans, syringes, fertilizers, pesticides and paint products by putting them in a hazardous materials collection site

Question 23

Transport in air

Answer 23

Release of the chemical at the source
Dispersion if chemical in the atmosphere
Deposition if the chemical in soil or water
The distribution of airborne pollutants may be limited by lack of wind, precipitation.
The pollutant will be depositors closer to its source if it is carried to the ground by rain or snow
It is hard to identify a pollutant that had travelled thousands of kilometres. Due to the movement of these chemicals it has become an international problem in which they are signing agreements to limit the amount of airborne pollutants.

Question 24

Transport in the soil

Answer 24

Water landing on a field or your yard does four things: Some evaporates Some soaks into the soil and is taken by plants Some runs into the street or stream Some soaks though the soil, moves downwards, dissolves substances in the soil and carries them along These substances are called leachate Composition of soil can affect this: if packed closely- harder to leachate, if not packed- most likely to leachate compared to packed clay Acids or other hazardous chemicals in the soil can neutralize organic substances such as broken down leaves that become organic material

Question 25

Photolysis

Answer 25

The breakdown of compounds by sunlight. Some substances degrade from exposure to light Ex. Photodegradable plastic: problem is that it will not break down if buried and out of sight from sunlight

Question 26

Phytoremediation

Answer 26

Green plants can be used to remove or degrade hazardous materials It reduces the concentration of harmful chemicals in the soul or groundwater Plants can be used to clean up metals, hydrocarbons, solvents, pesticides, radioactive materials, explosives and landfill leachates

Question 27

Dilution

Answer 27

Reduces the concentration of a pollutant by mixing the polluting substance with large quantities of air or water Ex. If you drip some bleach into a sink of water it will dilute into the water and spread the molecules

Question 28

Government regulations

Answer 28

Designed to protect consumers and reduce the risks of transporting,storing,using and disposing of hazardous materials

Question 29

Hazardous waste collection sites

Answer 29

Found in almost all of Alberta communities Wastes such as paints and fertilizers will be taken to theses sites for disposal Materials that cannot be recycled will be safely packaged in large containers where they are sealed with later

Question 30

Biodegration

Answer 30

Nature uses living things to clean up the environment Organisms such as earthworms, bacteria and Fungi help the biodegration of most organic substances degrade Algae live at the soil surface can use the broken down substance as organic compounds through photosynthesis for food Carbon atoms in these molecules can be used to build compounds such as carbohydrates and protein

Question 31

Transport in surface water

Answer 31

Potentially hazardous chemicals can enter the surface water from different sources such as air, groundwater, runoff from different sites, and the outflow from sewage treatment plants These chemicals can be dispersed throughout the surface water by these sources becoming attached to solids and can build to in lakes or river bottoms, affecting organisms We need to track and monitor the water continually due to this issue

Question 32

Nitrogen oxides

Answer 32

Also air pollutants which form smog and acid rain Like sulfur dioxide that affect our health by irritating the respiratory system and eyes Formed mainly from the combustion in vehicles

Question 33

Sulfur dioxide

Answer 33

Is an air pollutant that forms smog and acid rain Can affect respiratory system and irritate eyes Major source is industrial processes such as oil and gas industry, burning fuels such as coal, oil and natural gas Combine with oxygen to form nitrogen which is harmful to plants, animals and non living objects (major air pollutants)

Question 34

Pesticides have changed:

Answer 34

Because pesticides may be toxic scientists are designing new ones that last only one growing seasons and are broken down by bacteria Some insects have become resistant to pesticides and build their generation to e resistant as well Not all pesticides break down entirely in the environment, this causes the tissues of organisms to accumulate and cause serious health problems

Question 35

Spring acid shock

Answer 35

The Canadian Shield has been affected by acid precipitation which causes acid deposition In areas where acid precipitation is a problem it deposits into snow and ice in the winter. In the winter the snow and ice melt, therefor the water flows into streams and lakes... This is known as spring acid shock

Question 36

Carbon monoxide

Answer 36

A colourless and odour less gas and is known as the silent killer Main source is form human activity in noter vehicles Other sources include: combustion of wood, natural gas, industrial processes, airplanes and forest fires Dangerous because it reduces the amount of oxygen carried by the blood if inhaled and may result in headaches, sleepiness, chest pains, brain damage and even death

Question 37

Microbiological indicators

Answer 37

Organisms such as bacteria cause serious health problems if they are present in large numbers Samples of water are taken and tested for microorganisms... If the count is high the water requires additional treatment before it is considered for for humans

Question 38

Not a good indicator of water quality:

Answer 38

Clarity is not a good indicator of water quality because clear water can sometimes be harmful to humans and other organisms Ex: lakes affected by acid rain are crystal clear and lifeless

Question 39

The ozone layer

Answer 39

Occurs in high in the earths atmosphere15-20 km above the surface This ozone absorbs ultraviolet radiation which is a good thing As the ozone layer became thinner over the years, more UV radiation is allowed to reach the earths surface, which is a bad thing. This can cause a harmful effect in organisms: Increased risk if skin cancer in the cataracts in humans Plankton in the sea are sensitive to UV radiation could die off of exposed to large amounts. This would affect all the animals that feed on plankton

Question 40

Water quality is determined according to the 5 categories:

Answer 40

``` Human drinking water Recreation/swimming Livestock drinking water Irrigation Protection of aquatic life ```

Question 41

Parts per trillion

Answer 41

(ppt) is difficult and requires special costly equipment | Only extremely hazardous substances are measured to this level of concentration

Question 42

Aquatic environments

Answer 42

Diversity of all organisms decreases as acidity increases and dissolved oxygen decreases If the pH in the water is below 5.0 there will not be many fish Few insects and many worms may mean that the water contains little dissolved oxygen

Question 43

Factors that can affect the amount of dissolved oxygen is an increase in...

Answer 43

Phosphorus and nitrogen in the water This can cause increased growth of algae and green plants As most algae in green plants grit more die Bacteria is decomposing the dead material The bacteria increases the usage of dissolved oxygen in the water When the dissolved oxygen decreases many aquatic organisms decrease

Question 44

Catalyst converters

Answer 44

Are used in vehicles to convert carbon monoxide into carbon dioxide This creates a problem in the high levels of carbon dioxide being released, in increasing greenhouse gases and global warming

Question 45

Gypsum

Answer 45

A useful product that is recovered and used in manufacturing

Question 46

Greenhouse gases

Answer 46

Gases in the upper atmosphere which trap the heat are called greenhouse gases Water vapour, carbon dioxide, methane and nitrogen oxides are all greenhouse gases

Question 47

LD50

Answer 47

Used to compare toxins... LD stands for lethal does and 50 stands for 50% It is the amount of a substance that causes 50% of a group of test animals to die if they are given a specified does if a substance

Question 48

Global warming

Answer 48

When greenhouse gases accumulate in the atmosphere the overall temp of the earths surface Caused by: Human activities- Burning fossil fuels ect. Natural events-volcanic eruptions, forest fires ect. Some countries are attempting to reduce carbon dioxide emissions: Windmill farms- use power turbines rather than burning fossil fuels Forest projects- growing trees absorb the C02, reduces in environment

Question 49

Chlorofluorocarbons

Answer 49

Scientist Believe that the thinning of the ozone layer is a result of chemicals humans call chlorofluorocarbons (CFC's) Have been used in refrigerators, aerosol cans ect. When CFC's reach the upper atmosphere, UV radiation breaks chemicals down into substances such as chlorine that destroys the ozone. One chlorine atom can destroy 100000 ozone molecules International agreements have been signed by many countries in an attempt to reduce CFC's

Question 50

The enhanced greenhouse effect

Answer 50

Effect that is made greater by human activities such as burning fossil fuels and clearing land that add the gases in more concentrated amounts to the atmosphere Water vapour and then carbon dioxide contribute most to the enhanced greenhouse effect

Question 51

Ground level ozone

Answer 51

Layers of ozone in the upper atmosphere protect the earths surface from harmful chemicals However ground level ozone is a harmful pollutant Ozone is a odourless and colourless gas made up of 3 oxygen atoms At ground level the ozone reacts with oxygen, nitrogen oxides and volatile organic compounds Ozone pollution is a problem mainly in larger cities during the summer where there are many automobiles and industries Ozone is harmful to people with lung diseases ( asthma) Ground level ozone can seriously affect crops such as wheat, soybeans and onions Ozone can also cause materials such as plastic to deteriorate more rapidly

Question 52

What factors affect aquatic organisms

Answer 52

Chemical factors: These are indicators if water quality- Dissolved oxygen Acidity Heavy metals Plant nutrients such as nitrogen & phosphorus Pesticides Salts such as sodium chloride and magnesium sulfate The concentration if chemicals in the environment is usually measured in parts per million (ppm)

Question 53

Biological indicators

Answer 53

Scientists use organisms that live in water to help determine water quality These indicators can be: Microbiological indicators Aquatic invertebrates

Question 54

Lakes change due to...

Answer 54

They become cloudy in the summer because of excessive algae growth It reduces the oxygen content in the lake, effects the types of organisms that live there Ex. Trout is one of the first fish to die when the concentration of dissolved oxygen decreases

Question 55

Scrubbers

Answer 55

Are used on industrial and electrical generating plants to reduce sulfur dioxide emissions Use limestone (calcium carbonate) to convert sulfur dioxide to gypsum Combine with oxygen to form nitrogen which is harmful to plants, animals and non living objects (major air pollutants) Remove up to 99% of sulfur dioxide emissions

Question 56

The greenhouse effect

Answer 56

When radiant energy from the sun reached earths surface much of it is reflected back into space. Some of the energy is trapped near the Earths surface by a layer of gases that act like glass in a green house

Question 57

Monitoring air quality

Answer 57

Determined in two ways: Measuring levels of pollutants in the air Estimating the amount of emissions from pollution sources

Question 58

Dissolved oxygen

Answer 58

Is essential for the health if aquatic life such as fish, insects and micro-organisms Levels of dissolved oxygen depend on: Temp Turbulence due to wind or speed of water Amount of photosynthesis by plants and algae in water The number of organisms using up oxygen 5 milligrams per litre (5ppm) of dissolved oxygen will support most aquatic organisms

Question 59

Aquatic invertebrates

Answer 59

Invertebrates are animals without backbones are one group of indicator organisms Crustaceans, worms, insects and mollusks are invertebrates

Question 60

Carbon dioxide

Answer 60

Is naturally present in the air so it is not normally considered a pollutant

Question 61

Heavy metals

Answer 61

They can be toxic Mercury belongs to this group They are called heavy metals because they have a density greater than 5g/cm3 this means they are five times more heavier than an equal volume of water These metals accumulate into the bodies if organisms and cause health problems

Question 62

Humans change chemicals in the environment

Answer 62

Chemicals formed by human activities such as... Agricultural activities Solid wastes All form pollution! Waste water Fuel combustion Industrial processes

Question 63

pH scale

Answer 63

Measures the acidity if a substance | The pH of 13 means that a solution is basic- neither acidic or base

Question 64

Acids

Answer 64

Compounds that dissolve water to form a solution with a pH lower than 7

Question 65

Base

Answer 65

A compound that dissolves in water to form a solution with a pH higher than 7 Hair condition and household cleaning products are bases

Question 66

Pollution

Answer 66

Any change in the environment that produces a condition that is harmful to living things Ex: oil spills in a lake ecosystem affects organisms Smog from vehicles makes breathing difficult for humans and certain animals

Question 67

Carbohydrates

Answer 67

Organic molecules made up of atoms of carbon, hydrogen and oxygen

Question 68

What certain elements do for humans

Answer 68

Nitrogen: composition of proteins and nucleic acids found in all cells, growth and repair of tissues Phosphorus: composition if bones, teeth and DNA, many metabolic reactions Potassium: muscle contraction and never impulses Magnesium: composition of bones and teeth, absorption of calcium and potassium

Question 69

Animals break down food in two ways...

Answer 69

Mechanical- chewing food | Chemical- occurs in the mouth, stomach and small intestine with the help of enzymes that speed up chemical reactions

Question 70

Cellular respiration

Answer 70

Plants and animals need oxygen to carry our cellular respiration Cellars in your body consume food and oxygen to create C02 and energy Is a natural process that exists in both plants, animals and humans

Question 71

How many elements do our bodies need for normal growth?

Answer 71

25 elements | Form complex molecules that form sugar, starch, fat, oil, wax and proteins

Question 72

Optimum amount

Answer 72

Amount of a substance that provides an organism with the best health

Question 73

PH number

Answer 73

Indicates the acidity of a solution. It is a measure if the concentration of hydrogen ions in a solution

Question 74

PH meter

Answer 74

A tool that measures the pH of a substance that consists of using a probe which is submerged into the solution

Question 75

What nine elements are essential for the normal growth in plants?

Answer 75

Obtained by air or water: Carbon, hydrogen, oxygen Obtained by the soil: Nitrogen, phosphorus, potassium, magnesium, calcium, sulfur

Question 76

Hydrolysis

Answer 76

The breakdown or digestion if large organic molecules | A substance which is broken down had been hydrolyzed

Question 77

Processes and activities that may be harmful to living things include

Answer 77

Natural processes: forest fires, volcanoes | Human activities: gasoline, electricity and pesticides

Question 78

Nitrogen cycle

Answer 78

Plants can use nitrogen only when it is combined with other elements such as hydrogen and oxygen Air is about 78% nitrogen in the form of nitrogen gas Plants can't use "free" nitrogen directly. It had to be "fixed" into other compounds with other elements

Question 79

The concentration of usable nitrogen can be removed by..

Answer 79

Conversion- to free nitrogen by bacteria | Water- carrying dissolved nitrogen compounds deep into the soil, making it unavailable to plants

Question 80

Nitrogen can be added to souls that lack it by:

Answer 80

Planting nitrogen-fixing plants such as clover and alfalfa it add certain fertilizers

Question 81

Solid waste

Answer 81

Included garbage that is collected from: Households, industrial plants, commercial buildings, institutions, construction/demolition sites Some solid waste can be reused or recycled Most solid wastes are placed in landfill sites

Question 82

Osmosis

Answer 82

A passive transport method: process that is a type of diffusion, by which water molecules move across a cell wall/membrane from an area where there is more water molecules to an area where there are fewer water molecules

Question 83

Substrate

Answer 83

The material on which an organism moves or lives Ex. The sea anemone attaches itself it rocked where it can obtain rich nutrients grin the intertidal zone Bread mild obtains materials from the nutrient rich substrate that it lives on Some lichens and aka gar are able to obtain in nutrient poor substrates such as bare rocks or snow

Question 84

Acid rain

Answer 84

Industrial processes create many chemicals which go into our atmosphere... These chemicals dissolve in water droplets to from acids. When the acids fall back to earth it is known as acid rain Sulfur dioxide + water- sulfuric acid Nitrogen oxides + water- nitric acid Carbon dioxide + water- carbonic acid Causes lakes and streams to become acidic which harms aquatic life Causes buildings and monuments to deteriorate

Question 85

Organic compounds

Answer 85

Complex molecules that contain carbon Ex. Fossil fuels ( petroleum, natural gas and coal) Four most important classes: Carbohydrates, lipids, proteins and nucleic acids

Question 86

How do nutrients enter the plant

Answer 86

Through passive or active transport Passive: does not require the plant to use any energy Active: plants must use energy to move the molecules if nutrients in the direction opposite to diffusion. To maintain their concentrations, plants have to receive nutrients from the soil area and lower concentration in the roots

Question 87

Willow bark usage in the past/future

Answer 87

Used willow bark tea as a medicinal drink for F.N in the past A synthetic version of salicylic acid was developed by the Bater company and named it Aspirin

Question 88

Ingestion

Answer 88

The process if taking did into our bodies

Question 89

What certain elements do for plants

Answer 89

Nitrogen: composition if proteins and chlorophyll, leaf and stem growth Phosphorus: root and flower growth, cellular desperation and photosynthesis Potassium: stimulation of early growth, starch and protein production and sugar movement, disease resistance, chlorophyll production and tuber formation Magnesium: composition of chlorophyll structure

Question 90

Universal indicator

Answer 90

A tool that measures pH but is a mixture of indicators that change colour over a wife pH range

Question 91

Acid-base indicators

Answer 91

A tool that measures pH and are special substances which may change colour when paved in a solution Blues litmus paper turns red in an acid Red litmus paper turns blue in a base

Question 92

Plants produce sugar which is used as food, this requires?

Answer 92

Carbon dioxide and water

Question 93

Steps of nitrogen fixation

Answer 93

After nitrogen fixation occurs, plants use the nitrogen-containing compounds animals then eat the plants Animals use the nitrogen to make complex substances such as proteins Decomposes break down the large nitrogen compounds in the soil Nitrogen can moved from organisms and back into the soil several times Eventually some nitrogen compounds are broken down by bacteria in soil The nitrogen is released back into the environment as free nitrogen and the cycle begins again

Question 94

Benefits if acids

Answer 94

Vinegar is a weak acid Lemons are acidic Some plants grow better in acidic soils

Question 95

Proteins

Answer 95

Are used by organisms for growth and repair and as a source of energy A organic compound made up of units called amino acids

Question 96

Agricultural activities/ fertilizers

Answer 96

Fertilizers: substances that ene riches the soil so that plants will grow better Contain major nutrient elements such as: nitrogen, phosphorus and potassium The three numbers 15-30-15 means that the fertilizer contains 15% nitrogen 30% phosphorus 15% potassium Some fertilizers have an S on the label to indicate that it contains sulfur as a major ingredient Too much fertilizer can damage a crop or enter ponds water where it would damage the ecosystems

Question 97

Waste water

Answer 97

Sewage: waste water contain dissolved and un-dissolved materials from your kitchen, bathroom and laundry Septic tank: an underground container where bacteria break down The organic materials before they are moved into the soil Sewage treatment plant: treats waste from homes, businesses ect. Effluent: also known as treated waste water and is released into rivers or lakes

Question 98

Micronutrients

Answer 98

(Small) are needed in minor or trace amounts

Question 99

Hippocrates

Answer 99

Known as the father if medicine | Recommended willow bark be used to treat pain and fever

Question 100

Lipids

Answer 100

Fats, oils and waxes composed of mainly carbon, hydrogen and oxygen atoms

Question 101

Nitrogen fixation

Answer 101

Is the process if changing free nitrogen so that the nitrogen atoms can combine with other elements to form compounds that organisms can use Carried our mainly by bacteria in the soil The bacteria separate two nitrogen atoms that form nitrogen gas Some plants that are very good at nitrogen fixation include: beans, clover and alfalfa Once the nitrogen has been fixed, meaning that the nitrogen atoms have separated, the nitrogen can form compounds with other elements Lighting also convert nitrogen in the air to nitrogen compounds that plants can use

Question 102

Diffusion

Answer 102

A passive transport method: the movement of molecules from an area of higher concentration to one of lower concentration Some nutrients may move from an area if high concentration outside of the roots to an area of low concentration within the roots

Question 103

Macronutrients

Answer 103

Nutrients and elements that are needed in relatively large amounts

Question 104

Neutralization reaction

Answer 104

Produces water and a compound called salt An antacid is a mild base that reacts with stomach acid to neutralize it Acid lakes are sometimes treated with line to neutralize them

Question 105

Pesticides/agricultural

Answer 105

Chemicals that kill pests. A pest is an organism that harms people, crops or structures Herbicides- kill or control weeds Insecticides- kill or control insects Fungicides- kill fungi Cream problems such as being not selective which will kill both pest and non peer species Pests can sometimes become resistant to pesticides if they have been there for a long period of time

Question 106

Sanitary landfill

Answer 106

Prevent waste chemicals from going into the soil | Uses plastic liners and compacted clay to prevent the chemicals from going into the groundwater

Question 107

Nucleic acids

Answer 107

Are the largest and most complicated molecules found in living things All cells contain two important nucleic acids: DNA and RNA acids Play a major role in heredity and in controlling a cells activities

Question 108

Inorganic compounds

Answer 108

Substances that do not contain carbon | Ex. Baking soda