Water Quality Indicators

If a body of water has low levels of dissolved oxygen, what can most likely be concluded?

• water temperature is high

• water is polluted

• water is stagnant

• water is cold

What are some common sources of water pollution?

• Plastic waste and littering

• Agricultural runoff, industrial discharge, and sewage

• Airborne pollutants from vehicles

• Natural sediment from rivers

What is the significance of dissolved oxygen in water?

• It is essential for aquatic life; low levels can harm fish and other organisms.

• It helps in the filtration of water and removal of impurities.

• It increases the temperature of the water, promoting faster growth of algae.

• It is a byproduct of photosynthesis that has no impact on aquatic life.

A substance with a pH between 7-14 is considered _______.

• acidic

• neutral

• basic

• alkaline

What is turbidity?

• A measure of how clear water is, often affected by particles suspended in it.

• A method for measuring temperature in water.

• The amount of dissolved oxygen in water.

• The pH level of water.

Which source most likely contains a large amount of nitrates and is non-potable?

• water near agricultural land

• tap water from a municipal supply

• distilled water from a laboratory

• rainwater collected in a clean container

How can temperature affect dissolved oxygen levels in water?

• Warmer water holds less dissolved oxygen, which can be detrimental to aquatic life.

• Colder water holds more dissolved oxygen, which is beneficial for fish.

• Temperature has no effect on dissolved oxygen levels in water.

• Higher temperatures increase the solubility of oxygen in water.

What does a high level of nitrates in water indicate?

• It indicates the presence of harmful bacteria.

• It often indicates pollution from fertilizers or agricultural runoff.

• It suggests that the water is safe for drinking.

• It means the water is rich in minerals.

Water that has high turbidity is said to be ______.

• clear

• cloudy

• transparent

• pure

What is the pH scale used for?

• To measure temperature

• To measure how acidic or basic a substance is

• To measure the density of liquids

• To measure the volume of gases