Environmental Chemistry - Section 2

Question 1

What are indicator organisms?

Answer 1

Organisms that live in water and help determine water quality

Question 2

What are aquatic invertebrates?

Answer 2

Animals without backbones that live in water, such as insects or worms

Question 3

Concentration of chemicals in the environment are usually measured in ________

Answer 3

Parts per million (ppm)

Question 4

The level of dissolved oxygen depends on what?

Answer 4

Temperature of the water
Turbulence due to wind or speed of water
The amount of photosynthesis by plants and algae in the water
The number of organisms using up the oxygen

Question 5

Describe how temperature affects water quality

Answer 5

As temperature increases, dissolved oxygen concentration decreases

Question 6

Describe how turbulence affects water quality

Answer 6

As turbulence increases, dissolved oxygen concentration also increases

Question 7

Describe how photosynthesis affects water quality

Answer 7

As the amount of photosynthesis by green plants and algae increases, dissolved oxygen increases

Question 8

Describe how organisms affects water quality

Answer 8

As the number of organisms using the oxygen increases, the dissolved oxygen concentration decreases

Question 9

Describe how phosphorus and nitrogen content affects water quality

Answer 9

Large amounts of phosphorus and nitrogen can increase growth of algae and green plants

As more algae and green plants grow, more will then die, creating more organic matter

This will increase the number of bacteria which will use up the oxygen

Question 10

What is spring acid shock?

Answer 10

This occurs when acid deposits build up in snow and ice and then when that ice starts to melt, acid meltwaters flow into lakes and rivers

Question 11

Describe how pesticides affects water quality

Answer 11

Pesticides can remain in the soil and/or organisms which can find their way into the water
This can increase the toxicity of the water

Question 12

What are toxins?

Answer 12

Substances that produce serious health problems and even death

Question 13

What measurement do we use to compare toxins?

Answer 13

LD50

Question 14

What does LD50 stand for?

Answer 14

LD stands for lethal dose

50 represents 50% of a test population

Question 15

What is a heavy metal?

Answer 15

Metallic elements with a density of 5g/cm3 or more

These can be toxic to a wide range of organisms including humans

Question 16

What are some examples of heavy metals?

Answer 16

Mercury
Lead
Copper
Zinc
Nickel

Question 17

What are the two ways air quality can be determined?

Answer 17

By measuring the levels of pollutants in the air

By estimating the amount of emissions from pollution sources

Question 18

What is the major source of sulfur dioxide?

Answer 18

Industrial practices

Question 19

What are the two major air pollutants that form smog and acid rain?

Answer 19

Sulfur dioxide

Nitrogen oxides

Question 20

What is the major source of nitrogen oxides?

Answer 20

Combustion in vechicles

Question 21

What is carbon monoxide?

Answer 21

Called the silent killer because it is colourless and odourless

It is caused by an incomplete combustion or when there is not enough oxygen to form carbon dioxide

The main source is motor vehicles

When inhaled it reduces the amount of oxygen carried by the blood

Question 22

What is ozone?

Answer 22

Is an odourless, colourless has which protects the earth from the harmful UV rays. This layer is found above the earth in the upper atmosphere

Question 23

What is ground-level ozone?

Answer 23

Although ozone is commonly found up in the atmosphere, it can also be found at ground level
The ozone found at ground level is a harmful pollutant
The main source of ground level ozone is fuel combustion

Question 24

What are some of the problems ground- level ozone can cause?

Answer 24

It forms reactions between oxygen, and nitrogen oxides

It can cause breathing problems

It can affect crops such as wheat, soybeans, and onions

It can cause materials such as plastics to deteriorate more rapidly

Question 25

What is carbon dioxide?

Answer 25

It is naturally present in the atmosphere, so it is not considered a pollutant

The increasing number of carbon dioxide released into the atmosphere through a variety of emissions has become a concern

Question 26

What are some examples of greenhouse gases?

Answer 26

Water vapour
Carbon dioxide
Methane
Nitrogen oxide