topic one: Environmental chemistry Flashcards
Willow bark usage in the past/future
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
Hippocrates
Known as the father if medicine
Recommended willow bark be used to treat pain and fever
Plants produce sugar which is used as food, this requires?
Carbon dioxide and water
Cellular respiration
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
Processes and activities that may be harmful to living things include
Natural processes: forest fires, volcanoes
Human activities: gasoline, electricity and pesticides
Nitrogen cycle
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
Nitrogen fixation
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
Steps of nitrogen fixation
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
The concentration of usable nitrogen can be removed by..
Conversion- to free nitrogen by bacteria
Water- carrying dissolved nitrogen compounds deep into the soil, making it unavailable to plants
Nitrogen can be added to souls that lack it by:
Planting nitrogen-fixing plants such as clover and alfalfa it add certain fertilizers
Humans change chemicals in the environment
Chemicals formed by human activities such as…
Agricultural activities
Solid wastes All form pollution!
Waste water
Fuel combustion
Industrial processes
Pollution
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
Agricultural activities/ fertilizers
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
Pesticides/agricultural
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
Solid waste
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
Sanitary landfill
Prevent waste chemicals from going into the soil
Uses plastic liners and compacted clay to prevent the chemicals from going into the groundwater
Waste water
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
Acids
Compounds that dissolve water to form a solution with a pH lower than 7
PH number
Indicates the acidity of a solution. It is a measure if the concentration of hydrogen ions in a solution
Acid rain
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
Benefits if acids
Vinegar is a weak acid
Lemons are acidic
Some plants grow better in acidic soils
Base
A compound that dissolves in water to form a solution with a pH higher than 7
Hair condition and household cleaning products are bases
pH scale
Measures the acidity if a substance
The pH of 13 means that a solution is basic- neither acidic or base
PH meter
A tool that measures the pH of a substance that consists of using a probe which is submerged into the solution
Acid-base indicators
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
Universal indicator
A tool that measures pH but is a mixture of indicators that change colour over a wife pH range
Neutralization reaction
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
How many elements do our bodies need for normal growth?
25 elements
Form complex molecules that form sugar, starch, fat, oil, wax and proteins
Organic compounds
Complex molecules that contain carbon
Ex. Fossil fuels ( petroleum, natural gas and coal)
Four most important classes:
Carbohydrates, lipids, proteins and nucleic acids
What nine elements are essential for the normal growth in plants?
Obtained by air or water:
Carbon, hydrogen, oxygen
Obtained by the soil:
Nitrogen, phosphorus, potassium, magnesium, calcium, sulfur
Macronutrients
Nutrients and elements that are needed in relatively large amounts
Micronutrients
(Small) are needed in minor or trace amounts
Optimum amount
Amount of a substance that provides an organism with the best health
Inorganic compounds
Substances that do not contain carbon
Ex. Baking soda
Carbohydrates
Organic molecules made up of atoms of carbon, hydrogen and oxygen
Lipids
Fats, oils and waxes composed of mainly carbon, hydrogen and oxygen atoms
Proteins
Are used by organisms for growth and repair and as a source of energy
A organic compound made up of units called amino acids
Nucleic acids
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
What certain elements do for plants
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
What certain elements do for humans
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
How do nutrients enter the plant
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
Osmosis
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
Diffusion
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
Ingestion
The process if taking did into our bodies
Animals break down food in two ways…
Mechanical- chewing food
Chemical- occurs in the mouth, stomach and small intestine with the help of enzymes that speed up chemical reactions
Hydrolysis
The breakdown or digestion if large organic molecules
A substance which is broken down had been hydrolyzed
Substrate
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