Question

Acid precipitation kills the fish by the release of
A. Anticoagulants
B. Mercury
C. Aluminium
D. Both B and C

Answer 1

Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). It can have harmful effects on living as well as non-living organisms. Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids.

Complete step by step answer: Acid rain has been shown to have adverse impacts on forests, freshwaters and soils. It kills insects and aquatic life-forms as well as cause damage to buildings and has impacts on human health. Both the lower pH and higher aluminium concentrations in surface water that occur as a result of acid rain can cause damage to fish and other aquatic animals. At pH, lower than 5, most fish eggs will not hatch and lower pH can kill adult fish too. As lakes and rivers become more acidic biodiversity is reduced. Acid rain has eliminated insect life and some fish species, including the brook trout in some lakes, streams, and creeks in geographically sensitive areas. Soil biology and chemistry can be seriously damaged by acid rain. Some microbes are unable to tolerate changes to low pH and are killed. The enzymes of these microbes are denatured by the acid. The hydronium ions of acid rain also mobilize toxins, such as aluminium, and leach away essential nutrients and minerals such as magnesium.
Hence, the correct answer is option D.

Note: Impacts of acidic water and soil acidification on plants could be minor or major. Acidic water enters the plant and causes important plant minerals to dissolve and get carried away; which ultimately causes the plant to die of a lack of minerals for nutrition. Due to the corrosive nature of the acids, it damages both non-living things as well as living organisms. Acid rain poisons rivers and lakes.