Thread: Question about Aluminium

Were given this quote out of a textbook, and we have to explain what is mean't by Aluminium is "mobilised" from minerals into water. But i'm not sure what it means.
Do you guys have any idea?

"Aluminum is a naturally occurring element that is toxic to fish. It is mobilized from minerals into the water when acidity levels increase. The decrease in pH is the result of the acid in rainwater and other precipitation removing the stream?s acid neutralizing capacity or ANC. Measurement of ANC is an important means of establishing the vulnerability of a stream or lake to acid rain."

also...

Could aluminium poisoning be a problem in lakes affected by acid rain? Why would that be?

I've read your stuff very quickly, I think I understood the main idea.

we have to explain what is mean't by Aluminium is "mobilised" from minerals into water. But i'm not sure what it means.
Do you guys have any idea?

The acid of the rains affects lakes. It produces the separation of the aluminium from the rocks (minerals) into the water. Then it becomes a problem for the fishes that live in the lake, who are affected by the freed aluminium. So mobilised means that normally aluminium doesn't separates from minerals, but it does due to acid rains.

Could aluminium poisoning be a problem in lakes affected by acid rain? Why would that be?

Of course yes. The fishes are affected, which means that everything that eat fish is also affected. So even humans that fish fishes and eat them may be affected by aluminium. Therefore yes, it turns out to be a problem.

Originally Posted by Seza<3

Were given this quote out of a textbook, and we have to explain what is mean't by Aluminium is "mobilised" from minerals into water. But i'm not sure what it means.
Do you guys have any idea?

"Aluminum is a naturally occurring element that is toxic to fish. It is mobilized from minerals into the water when acidity levels increase. The decrease in pH is the result of the acid in rainwater and other precipitation removing the stream?s acid neutralizing capacity or ANC. Measurement of ANC is an important means of establishing the vulnerability of a stream or lake to acid rain."

also...

Could aluminium poisoning be a problem in lakes affected by acid rain? Why would that be?

1. Perhaps you should start a web-search about environmental water treatment.

2. Al produces a layer of Al2O3 which protects the Al against further oxidation

3. If the pH value of water is between 5.0 and 5.5 the concentration of Al-ions increses rapidly. The Al-ions form a layer on the gill of the fishes so the respiration is disturbed heavily.

4. A concentzration of 1.5 mg/l is fatal for trouts so they are used as a bio-indicator to judge the quality of water.

5. High Al-ion concentrations are damaging to human nerves, lungs and kidneys.