You have gone into the field to take water samples from two lakes in your town. You note the following observations:
- Lake A contained many fish swimming in its waters.
- Lake B had very few fish swimming in its waters, and a few dead fish floating on the water.

You return to your lab and take [tex]$pH$[/tex] readings for each sample. Think about how acids and bases would affect the water quality in the two lakes.

Which set of [tex]$pH$[/tex] data would you expect to see based on your observations?

A. Lake A: [tex]$pH = 4.5$[/tex]; Lake B: [tex]$pH = 7.5$[/tex]
B. Lake A: [tex]$pH = 8.3$[/tex]; Lake B: [tex]$pH = 3.7$[/tex]
C. Lake A: [tex]$pH = 6.6$[/tex]; Lake B: [tex]$pH = 6.8$[/tex]
D. Lake A: [tex]$pH = 10.2$[/tex]; Lake B: [tex]$pH = 1.7$[/tex]



Answer :

To determine the appropriate pH data for the lakes based on your observations, let's analyze the conditions and pH implications for the water samples.

1. Observations Analysis:
- Lake A: Many fish swimming in the water suggest that the water quality of Lake A is likely good and conducive for aquatic life.
- Lake B: Few fish swimming and a few dead fish floating indicate poor water quality, which might be due to extreme pH levels making the environment uninhabitable.

2. Review of pH and Water Quality:
- Healthy lakes generally have pH levels close to neutral (around pH 7) as this range is suitable for most aquatic life.
- Acidic water (pH < 7) might be harmful if the pH is too low.
- Basic (alkaline) water (pH > 7) might be harmful if the pH is too high.
- Extremes (very low pH or very high pH) typically signify poor water quality.

3. Potential pH Data Sets:
- Lake A: pH = 4.5; Lake B: pH = 7.5
- Lake A with pH 4.5 is quite acidic, which is not favorable for fish to thrive.
- Lake B with pH 7.5 is slightly basic but close to neutral, and it should not cause significant fish mortality.
- Lake A: pH = 8.3; Lake B: pH = 3.7
- Lake A with pH 8.3 is mildly basic and might still support fish life.
- Lake B with pH 3.7 is quite acidic, which could result in the poor water quality observed.
- Lake A: pH = 6.6; Lake B: pH = 6.8
- Both values are close to neutral, suggesting neither lake would exhibit extreme conditions impacting fish life significantly as observed.
- Lake A: pH = 10.2; Lake B: pH = 1.7
- Lake A with pH 10.2 is highly basic, which could still support some fish but is getting to the extreme high range.
- Lake B with pH 1.7 is highly acidic, likely causing the poor water quality and the mortality of fish observed.

Considering the observations and the impact of pH on water quality and aquatic life:

- Lake A should exhibit a condition that supports numerous fish, whereas Lake B should exhibit an extreme condition leading to poor water quality and fish mortality.
- Of the given options, Lake A with pH 10.2 (high but less detrimental) and Lake B with pH 1.7 (highly acidic and harmful) aligns best with the observed conditions.

Therefore, based on the observations and reasoning, the expected pH data is:
- Lake A: pH 10.2
- Lake B: pH 1.7

Other Questions