Environmental Chemistry

Unit C

Key TermsUse the spaces below to define the key terms in your own words.

1.1Key Terms Textbook Definition Drawing / In my own words

Elements

Nitrogen Fixation

Pollution

Fertilizer

Pesticides

Pest

Issue

Sewage

Septic Tank

Sewage Treatment Plant

Effluent

Storm Sewers

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Fossil Fuels

“Sour” Gas

1.2Key Terms Textbook Definition Drawing / In my own words

Acid

pH

Base

Neutral

Neutralization

1.3Key Terms Textbook Definition Drawing / In my own words

Organic Compounds

Inorganic Compounds

Nutrients

Macronutrients

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Micronutrients

Optimum Amounts

Carbohydrates

Lipids

Proteins

Enzymes

Nucleic Acids

1.4Key Terms Textbook Definition Drawing / In my own words

Diffusion

Osmosis

Active Transport

Passive Transport

Substrate

Pick a term you struggled with. Come up with a definition that even a grade 3 student could understand in the space below.

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CHAPTER 1 – THE ENVIRONMENT IS MADE UP OF CHEMICALS THAT CAN SUPPORT OF HARM LIVING THINGS

Environmental chemistry is the study of how ___________________ substances make up the ________ around us. Chemicals are part of the process in all natural _________________ and processes.

Changing the ______________________ and _____________ of chemicals present in our environment will have an impact on our _______________________ and the distribution and abundance of living things in the environment.

1.1 – CHEMICALS IN THE ENVIRONMENT

Our ______________________ is made up of different chemicals. These chemicals will either _____________ or ___________ living things.

The Nitrogen Cycle

Nitrogen is an important _____________ for living things. It can be found in _____________, amino acids, _________________, etc. In the nitrogen cycle,

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nitrogen makes its way through our __________________ in different forms. (http:// www.youtube.com/watch?v=DP24BceOwt8 )

Nitrogen is found as an element in the _________. However, ____________ cannot use nitrogen in this form, so it must be _____________________ into another form to be useful.

Nitrogen _____________ is the process by which some bacteria and algae separate nitrogen atoms from each other so they can form __________________ with hydrogen and oxygen.

1. Atmospheric nitrogen is fixed by ______________ in the soil2. Plants use the ____________ nitrogen3. _________________ then eat the plants and use nitrogen to make new molecules,

like ________4. Animal and plant _____________ is then used by _______________________ who

release nitrogen back into the soil5. This nitrogen is again used by ______________ to start the cycle over; some

nitrogen is released back into the ________________________

Processes that Affect Environmental Chemicals

The nitrogen cycle is an example of how environmental chemicals change. Can you think of at least 1 other example?

Both _________________ and ___________________ processes can change chemicals in the environment. For example, both exhaust from vehicles and forest fires can create an excess of carbon dioxide in the air and produce smog, which makes it difficult to breathe for some organisms.

Human impacts are especially interesting to many people because of _________________. Pollution is any change in the ___________________ that produces a condition that is ____________________ to living things.

Human Activities

Agriculture

Farmers need to have an understanding of environmental chemistry

Many people use _______________ which enrich soil so that plants will grow better

However, too much fertilizer can _______________ organisms, since the excess chemicals get into the ____________ _____________ and are even harmful to the crop itself

Not only do humans use fertilizer, we also use _________________ to kill unwanted organisms.

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A pest is an organism that _____________ people, crops, or _______________ Some pesticides are not ___________________, they kill both pest and non-pest

species. What are the implications?

Solid Wastes

Chemicals are ____________________ into the environment when we ______________ of solid waste or wastewater (sewage/drain water)

This includes _________________ collected from households, industry and commercial buildings.

Some solid waste can be _______________; however, most of it ends up in _________________ sites

In a _____________________ landfill site, wastes are spread and compacted by bulldozers before they are ___________________ by soil

These landfills use ____________________ liners and compacted _____________ to prevent drainage of waste products into the soil and groundwater

Waste Water

Much wastewater is produced in our _____________ and is then treated at a wastewater treatment plant

http://www.youtube.com/watch?v=- WWwmYrJkac

Fuel Combustion

Coal, oil, and natural gas are _______________ _________

These are non-renewable resources When fossil fuels are burned, they produce large

amounts of ____________ ______________ and ______________ vapour

This burning of fossil fuels also releases _______________________

These can cause acid rain and other ____________________ in our environment

Homework Assignment – Check and Reflect Pg. 190

1. What role do decomposers play in the nitrogen cycle?

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2. What is pollution? Give three examples of chemical pollution.

3. What do the numbers on the fertilizer label to the right indicate?

5. How do sanitary landfill sites prevent chemicals from moving into the groundwater?

6. Describe two ways that nitrogen is removed from an ecosystem.

7. What pollutants are released from fossil fuel combustion?

8. Why do farmers use fertilizers?

9. Why does sewage need to be treated?

11.Identify two issues related to human activities that change chemicals in the environment. For each one, explain (in 2-3 sentences) why it is considered to be an issue.

1.2 – ACIDS AND BASES

An ___________ is a substance that dissolves in water to form a solution with a _______ lower than ____. The pH of a solution is a measure of the __________________ of hydrogen _______ in that solution.

A _________ is a compound that dissolves in water to form a solution with a _______ higher than ____.

A ___________ substance has a pH of _____ while in solution.

The pH Scale

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________________ is measured according to pH. The pH scale ranges from a pH of ______________ (in most cases).

The difference between pH is on a ___ - fold scale. For example: a solution with a pH of 3 is 10 times more acidic than a solution with a pH of 4.

Measuring pH

Acid-base __________________ or pH meters can be used to measure the pH of a solution. An acid-base indicator will change _____________ depending on what the _________ of the solution is.

Neutralization

A __________________________ reaction is a reaction between an _________ and a ___________ in which __________ and a ________ is formed.

Neutralizing the Effects of Acid Rain

Ordinary rain water is ___________ acidico This is because there is already a __________ amount of CO2 in the

__________ which will react with rain water to form a very _________ acid (pH = ~5.6)

However, with an increase of _________________ in the atmosphere (especially SO2, SO4, and NO3), ________ rain has become a major problem

o Some areas of Canada have rain with a pH as low as 3

Homework Assignment – Check and Reflect Pg. 195

1. Define the terms “neutral solution,” “acid,” and “base.”

2. State whether each substance below refers to an acid, a base, or a neutral solution.

a) Solution A turns blue in litmus paper red

b) Solution B has a pH of 10

c) Pure water has a pH of 7

d) Solution C neutralizes an acid

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3. List three human activities that release chemicals that produce acid rain. For each one, identify the chemicals that are released and the acids they form.

4. What is the scientific meaning of the following sentence? Lemon juice is an acid.

5. You have been asked to determine the pH of a solution. Explain why using a pH meter or a universal indicator is better than using litmus paper.

6. Predict what the chemical products will be if sulfuric acid (H2SO4(aq)) and sodium hydroxide (NaOH(aq)) are mixed together.

7. Suppose that there is a small lake on property that you own. The pH of the water in the lake has increased to 8.1 because of human activities.

a) How could you make the water neutral?

b) What environmental changes might you expect following the neutralization of the lake water?

1.3 – COMMON SUBSTANCES ESSENTIAL TO LIVING THINGS

Nutrients

All living things need _____________ to survive

Nutrients are _______________ and ________________ that organisms need for ___________, _______________ and ___________________

Some nutrients are needed in larger amounts than others The nutrients that are needed in _____________ amounts are called

______________________ (“macro-“ means large) The nutrients that are still essential but needed in much ______________

amounts are called ________________________ (“micro-“ means very small)

Nutrient In plants, it’s important in: In animals, it’s important in:Nitrogen (N) - Composition of proteins and

chlorophyll- Composition of proteins and

nucleic acids

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- Leaf and stem growth - Growth and repair of tissuesPhosphorous (P)

- Root and flower growth- Cell respiration and

photosynthesis

- Composition of bones, teeth, and DNA

- Many metabolic reactionsPotassium (K)

- Stimulation of early growth- Starch and protein production

and sugar movement- Disease resistance- Chlorophyll production and

tuber formation

- Muscle contraction and nerve impulses

Magnesium (Mg)

- Composition of chlorophyll structure

- Photosynthesis

- Composition of bones and teeth- Absorption of calcium and

potassiumCalcium (Ca) - Cell wall structure

- Cell division- Composition of bones and teeth- Blood clotting- Muscle and nerve function

Sulfur (S) - Production of fruits and grains - Protein synthesis- Enzyme activation- Detoxification

Plant Nutrients

Without these elements, plants would not be able to _____________, or would not do very well

http:// www.youtube.com/watch? v=ctMTltWG1GU

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Optimum Amounts

There can be “too much of a good thing”!!!

In all living organisms __________________ are essential, but having too much of a nutrient can be just as ____________________ as not having enough of the nutrient. Examples:

Selenium is a micronutrient that is required in trace amounts in our diets. Too much of it can cause harmful effect, but too little of it can also be harmful.

High level of potassium in the soil can be harmful to plants by preventing them from absorbing magnesium. But potassium is important to plants for growth and production of important compounds.

There is an _______________ amount!

An _______________ amount is the amount of that ______________ that provides the organism with the _________ health.

Organic and Inorganic Compounds

Our bodies need about 25 elements to _________________ our health and normal growth. These elements can be found in two types of compounds: _____________ and ___________________ compounds.

____________________ compounds are compounds whose molecules contain _____________. Exceptions: CO, CO2, carbonates, and cyanides – these are all inorganic.

____________________ compounds are compounds whose molecules do _______ contain ______________.

Types of Organic Molecules

There are 4 main types of organic molecules essential for all living things:

1. ________________ 2. _________________3. ____________________4. ___________________

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Carbohydrates

Carbohydrates are organic molecules made up of ______________, _________________ and ___________________

They can be simple molecules, such as _____________, or large molecules, like _________, glycogen, and cellulose

Glucose is a simple sugar that is made during photosynthesis

o It is a simple ____________________ Cellulose, starch and glycogen are _______________

carbohydrates that are made up of many ________________ molecules linked together

Lipids

___________, __________ and waxes are lipids These are compounds made up of many __________________, _________________

and _______________ atoms These are used for long-term _________________ storage

Proteins and Amino Acids

Proteins have many functionso They are used for __________ and repair, and as a source

of _____________o Main component of __________________

Proteins are organic compounds made of smaller units that are called ______________ _____________

Each _______________ has its own number and make-up of amino acids

Nucleic Acids

The _____________ and most ________________ molecules found in living things

______ is an example of a nucleic acid They are made up of three sub-parts

o ______________o ______________o _______________

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Homework Assignment – Check and Reflect Pg. 203

1. Define the term “organic compound.” Give two examples of these compounds.

2. List four elements that are macronutrients in plants. Explain their importance in plants and in humans.

3. What is a micronutrient? Give an example.

4. What elements are found in the following compounds?a) Carbohydrates

b) Proteins

c) Lipids

d) Nucleic acids5. Imagine that your favourite house plant is growing well but it is not flowering. A

friend suggests that your plant may be lacking phosphorous. Is that a possibility? Explain your answer.

6. Explain the term “optimum amount” using one of the following as an example: potassium for plants or selenium for animals.

7. Which term in each of the following groups of four terms includes the other three?

a) Carbohydrate, glycogen, starch, glucose

b) Sugar, DNA, phosphate, nitrogen-containing base

c) Fats, waxes, oils, lipids

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8. Suppose you are a farmer and your crop is not growing as well as it has in the past. You notice that the lower leaves of the plants are turning yellow. Recall that chlorophyll gives leaves their green colour and is important in photosynthesis. Use the table on pg. 197 of your textbook to help you answer the following questions:

a) What nutrient deficiencies might be causing this problem?

b) What would be your next step to solve the problem?

9. A sample solution was sent to a laboratory for examination. When Benedict’s solution was added, and the sample was heated, a red precipitate formed. When Biuret solution was added, the solution remained blue. What substance was identified in the solution?

1.4 – HOW ORGANISMS TAKE IN SUBSTANCES

Uptake of Substances by Plants

Plants need nutrients just like animals, but unlike animals they can’t move around to get them. So how does this work?

Plants use _____________ and ______________ transport through their roots and leaves

____________________ transport is the movement of molecules along a _______________________ ____________________

__________________ transport requires ____________________ to move molecules

Diffusion

______________ is the movement of particles along a concentration gradient

Particles move from an area of _______________ concentration to an area of ____________ concentration

Osmosis

Osmosis is a special type of diffusion that involves the movement of ______________ along a ______________________ gradient

The water moves from the __________ into the __________ because the concentration of

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______________ is much higher in the roots, and therefore the concentration of solvent (___________) is low

Active Transport

_________________ transport moves molecules ____________________ a concentration gradient

o This requires ____________________ Plants use active transport to get _________________ from the soil

o There is a large concentration of nutrients in the roots compared to the soil, so this is against a concentration gradient

Ingestion and Absorption of Nutrients by Animals

Animals get their essential nutrients from the ___________ they breathe and the food they _____________. The food is broken down _____________________ (chewing) and _________________ (stomach and intestines) and absorbed into the bloodstream.

Nutrients and Substrates

Where organisms ____________ affects how and when they obtain nutrients. There are many adaptations that help organisms obtain nutrients. List 3 specific examples below.

A _________________ is the material on which an organism lives. Some organisms are _____________ to their substrates (ex. plants, algae, lichen), while others move around.

Homework Assignment – Check and Reflect Pg. 209

1. Define the following terms:

a) Diffusion

b) Osmosis

c) Active transport

3. What happens to food when you ingest it?

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4. What effect do hydrolysis enzymes have on the rate at which large organic molecules break down?

5. Plants take in water from the soil. Why does the water move from the soil into a plant’s roots?

6. How is the process of diffusion similar to active transport? How are the two processes different?

7. Why are the algae that live on snow able to survive high in the Rockies in early summer?

Section Review – Pg. 211

1. Define the term “macronutrient” and give three examples.

2. List two roles of potassium in plants and two roles in humans.

3. Identify two elements that are known to enhance plant growth but that limit growth if too little or too much is available.

4. What is a sanitary landfill?

5. Use an example to help explain what a neutralization reaction is.

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6. Explain the difference between organic and inorganic compounds. Give one example of each.

7. Match the organic molecules with the elements that they are made up of.

Carbohydrates C, H, N, OProteins C, H, ONucleic acids

C, H, O, N, P

8. a) What do the numbers 10-0-0 on a fertilizer label mean?

b) What type of growth does this fertilizer promote?

9. a) Why do farmers use pesticides?

b) Why do some people want farmers to use lower amounts of pesticides?

10.What types of organic molecules make up a hamburger? In your answer, name the part of the hamburger that includes each type of compound. Include the bun, the meat patty, and everything on the burger.

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