Chemicals In The Environment 1.1 Flashcards
All living things are formed or depend on what to survive?
Chemicals
All chemical compounds are made up of what?
Elements
Elements are _____ __________ that cannot be ______ __________ into other substances.
pure substances
broken down
What is nitrogen fixation?
The process of changing free nitrogen so that the nitrogen atoms can combine with other elements to form compounds that organisms can use.
A pro and a con of CO2 release?
Pro: CO2+water are needed by plants to produce food
Con: CO2 contributes to the Greenhouse Effect
What is pollution? Example of?
Any change in the environment that produces a condition that is harmful to living things. For example, smog caused by vehicle exhaust emissions is pollution because it makes it hard for people and other animals to breathe. Forest fires produce similar chemical pollution.
What is the nitrogen cycle?
Nitrogen fixation happens in plants, then animals eat the plants. Their bodies use the nitrogen in the compounds to make more complex substances, such as proteins.
Decomposers break down these large nitrogen-containing molecules in dead organisms and animal waste into simpler nitrogen compounds in the soil.
Lightning converts gas so it can combine to form usable compounds.
This nitrogen is released back into the air as free nitrogen, and the cycle begins again.
What is cellular respiration
*Is a natural process
*Give your body food as “fuel” and air rich in oxygen, to give you energy, for the bodies processes.
*Produces CO2 as a product
What is an issue?
Any subject of importance about which people have strong, conflicting points of view.
What is a fertilizer? Example of?
A fertilizer is a substance that enriches soil so that plants will grow better.
For example, potassium is essential to plant growth. If a soil is low in potassium, plants cannot grow well in it. The soil must be enriched by adding a potassium fertilizer.
What is a pest?
An organism that harms people, crops, or structures.
What are pesticides?
Pesticides are chemicals used to kill pests.
What are herbicides?
Kill or control weeds.
What are insecticides?
Kill or control insects.
What are fungicides?
Kill fungi.
Fertilizers are described by the major nutrient elements they contain, and these elements are?
Nitrogen, phosphorus, and potassium.
The three numbers 15–30–15 on the label
indicate that this fertilizer contains what?
15% nitrogen compounds, 30% phosphorus compounds, and 15% potassium compounds.
Some fertilizers have a fourth number and the letter “S” on the label to indicate that they
contain _______ as a major ingredient.
sulfur
Fertilizers may come from what?
Natural sources or synthetic chemicals.
Too much _______ may even damage the crop and organisms it’s supposed to help.
fertilizer
If fertilizer enters ponds, streams, lakes, or rivers, it may damage those ecosystems by doing what?
Changing concentration of chemicals.
A pesticide that kills both pest and non-pest
species is what?
Some pesticides are not selective—they
Chemicals may be introduced into the environment when we dispose of what?
Solid waste or wastewater.
Solid waste includes what? Some solid waste can be reused or recycled, but most of it is placed where?
The garbage that is collected from households, industrial plants, commercial buildings, institutions, and construction and demolition sites. It includes large items, such as machinery, all the way down to small items, such as the caps on plastic drink bottles.
Landfill sites
Some hazardous wastes are burned in special plants called what. What do they do and what can they contribute to?
Incinerators. They burn at very high temperatures. Emissions from incinerators may contribute to air pollution.
Sanitary landfill sites are specially built to prevent ______ ________ from moving into the soil.
waste chemicals
Sanitary landfills are what?
They use plastic liners and compacted clay to prevent these solutions (As rainwater or groundwater moves through solid waste, it can dissolve or corrode some items.) from entering the soil and the groundwater.
What is sewage?
Wastewater containing dissolved and undissolved materials from your kitchen, bathroom, and laundry.
Sewage moves through pipes into a septic tank in rural areas or to a sewage treatment plant in
towns and cities. What is a septic tank?
An underground container where bacteria break down the organic materials before they are moved out to the soil.
A sewage treatment plant does what?
Treats wastes from homes, businesses, industries, and institutions.
What is effluent?
Treated wastewater and is released into rivers or lakes.
If the municipal sewage system cannot handle a large quantity of rain water from street drains, that water may go directly into a river or lake through large pipes called what?
storm sewers
What are fossil fuels?
Coal, oil, and natural gas are called fossil fuels because they formed from dead plants and animals.
What are hydrocarbons?
They are called hydrocarbons because they are
mainly made up of the elements hydrogen and carbon.
When fossil fuels are burned in homes, vehicles, and industrial plants, they produce what?
Large amounts of carbon dioxide and water vapour.
The general reaction equation for this (burned fossil fuels) combustion reaction is:
Hydrocarbon + oxygen → carbon dioxide + water + energy
The equations below show what happens in the combustion of methane (in natural gas) and propane.
CH4(g) + 2O2(g) → CO2(g) + 2H2O(g)
methane + oxygen → carbon dioxide + water vapour + energy
C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g)
propane + oxygen → carbon dioxide + water vapour + energy
A common industrial process in Alberta is what?
Natural gas processing
Natural
gas is composed of compounds such as methane, ethane, propane, and
butane. It also contains nitrogen gas, carbon dioxide, hydrogen sulfide,
helium, and traces of metals such as mercury.
Natural gas is processed to separate its components for different uses.
Methane, propane, and butane are all derived from natural gas and are
used primarily for heating. Ethane is used in plastics such as
polyethylene.
Natural gas is also processed to eliminate unwanted substances such
as hydrogen sulfide, a poisonous chemical. Natural gas that contains
hydrogen sulfide is called “sour” gas. If no hydrogen sulfide is present,
the gas is considered “sweet.”
The process for removing hydrogen sulfide produces sulfur dioxide
gas and pure sulfur. Since the 1970s, natural gas processing plants in
Alberta have been required by law to restrict their sulfur dioxide
emissions. They now recover more than 99% of the pure sulfur for use in
manufacturing sulfuric acid. Sulfuric acid is used in making fertilizers,
steel, synthetic fibres, and paints.
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