8.E.1.3 Water

Pure water is neutral. If water is neither an acid nor a base, what is the pH of water?

• 0

• 7

• 10

Which best describes the relationship between temperature and dissolved oxygen in a lake?

• As temperature increases, dissolved oxygen increases.

• As temperature increases, dissolved oxygen decreases.

• As temperature decreases, dissolved oxygen decreases.

• A change in temperature has no effect on dissolved oxygen.

If a large amount of fertilizer enters a lake, which will most likelyhappen?

• The fish population in the lake will increase.

• The temperature of the lake water will increase.

• The number of fish dying in the lake will increase.

• he available food supply for the fish in the lake will increase.

Which best explains why a scientist would use nets to capture and count organisms in a river?

• to measure pH

• to measure turbidity

• to measure biodiversity

• to measure temperature

What does pH measure?

• acidity/alkalinity

• dissolved oxygen

• nutrient level

• turbidity

Which would be the most likely cause of large numbers of fish dying in a stream?

• a lack of nitrogen

• high levels of mercury

• decreased carbon dioxide

• low dissolved oxygen concentration

Which is the greatest impact of large quantities of sediment flowing into North Carolina’s rivers and streams?

• Sediment poisons fish.

• Sediment prevents light from reaching plants.

• Sediment interferes with the ability for fish to find mates.

• Sediment increases the depth of rivers and streams, reducing the amount of flowing water.

Which best determines the health of a lake used as a source of freshwater?

• its depth and width

• its temperature and pH

• its location and depth

• its temperature and depth

If a body of water has high turbidity levels, what can most likely be concluded?

• It has a low pH

• It is unsafe to drink

• It is too hot to drink

• It contains lots of chemicals

Which will occur if humans continue to overload water systems with excess nutrients?

• chemosynthesis

• eutrophication

• nitrification

• photosynthesis