Environmental Chemistry Unit Review

You sample a stream and find the following:
∎19 leeches
∎7 freshwater worms
∎8 midge larvae
∎15 mosquito larvae
What can you determine about the health of the stream?

• The stream is extremely healthy and has little to no pollution.

• They stream has some pollution.

• The stream is extremely unhealthy and heavily polluted.

• There is no way to determine how healthy this stream is based on this information.

Tags

NGSS.MS-LS2-4

Given this data, the scientist inferred that immediately downstream from the workers' housing complex, the treated wastewater…

• had no effect on the quality of the river water

• carried non-toxic chemicals into the river water

• improved the abiotic conditions of the river water

• would have an effect on the diversity of living organisms

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Samples of the water are collected from different parts of the river, P, Q, R and S. Which one of the following graphs correctly reflects the number of organisms found in each part of the river?

• 
• 
• 
• 

Tags

NGSS.MS-ESS3-4

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Much of the power generated in Alberta comes from coal-fired plants. The burning of coal is the leading cause of…

• Carbon dioxide pollution

• Nitrogen dioxide pollution

• Sulphur dioxide pollution

• All of the above

Tags

NGSS.MS-ESS3-3

Climate change has become an environmental issue. Which of the following chemicals is one of the greatest contributors to climate change?

• DDT

• CO₂

• CFC

• O₂

Tags

NGSS.MS-ESS2-6

NGSS.MS-ESS3-5

What human activity leads to acid rain?

• burning fossil fuels

• Fertilizer use

• Pesticide use

• CFCs

Tags

NGSS.MS-ESS3-4

The ozone layer protects us from

• UV rays

• CFCs

• Increased atmospheric heat

• Decreased atmospheric heat

What is the concentration, in ppm, of lead in a 6 kg (6 000 000 mg) solution that contains 12 mg of lead?

• 1.0 ppm

• 2.0 ppm

• 3.0 ppm

• 4.0 ppm

LD50 is the standard used to compare the toxicity of any substance. LD50 means that…

• 50 animals would die if they consume a dose of the toxic substance

• 50% of the animals would die if they consume a dose of the toxic substance

• 50% of the test population of animals would die if they consume a specific dose of the toxic substance.

• 50% of the test population of animals would die if they consume any amount of the toxic substance

Tags

NGSS.MS-PS1-2

What is the concentration of a solution in parts per million if 0.02 grams of NaCl is dissolved in 1000 grams of water?

• 2 ppm

• 20 ppm

• 200 pm

• 0.2 ppm