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  2. Acid rain - Wikipedia

    en.wikipedia.org/wiki/Acid_rain

    Acid rain is rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH).Most water, including drinking water, has a neutral pH that exists between 6.5 and 8.5, but acid rain has a pH level lower than this and ranges from 4–5 on average.

  3. Limestone - Wikipedia

    en.wikipedia.org/wiki/Limestone

    Limestone (calcium carbonate CaCO 3) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of CaCO 3. Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place ...

  4. Soil acidification - Wikipedia

    en.wikipedia.org/wiki/Soil_acidification

    The donor can be an acid, such as nitric acid, sulfuric acid, or carbonic acid. It can also be a compound such as aluminium sulfate , which reacts in the soil to release protons. Acidification also occurs when base cations such as calcium , magnesium , potassium and sodium are leached from the soil.

  5. Lime (material) - Wikipedia

    en.wikipedia.org/wiki/Lime_(material)

    Pure lime is soluble in water containing carbonic acid, a natural, weak acid which is a solution of carbon dioxide in water and acid rain so it will slowly wash away, but this characteristic also produces autogenous or self-healing process where the dissolved lime can flow into cracks in the material and be redeposited, automatically repairing ...

  6. Liming (soil) - Wikipedia

    en.wikipedia.org/wiki/Liming_(soil)

    Liming is the application of calcium- (Ca) and magnesium (Mg)-rich materials in various forms, including marl, chalk, limestone, burnt lime or hydrated lime to soil. [1] In acid soils , these materials react as a base and neutralize soil acidity .

  7. Weathering - Wikipedia

    en.wikipedia.org/wiki/Weathering

    It takes place when rainwater combines with carbon dioxide to form carbonic acid, a weak acid, which dissolves calcium carbonate (limestone) and forms soluble calcium bicarbonate. Despite a slower reaction kinetics , this process is thermodynamically favored at low temperature, because colder water holds more dissolved carbon dioxide gas (due ...

  8. Lime kiln - Wikipedia

    en.wikipedia.org/wiki/Lime_kiln

    The theoretical heat (the standard enthalpy) of reaction required to make high-calcium lime is around 3.15 MJ per kg of lime, so the batch kilns were only around 20% efficient. The key to development in efficiency was the invention of continuous kilns, avoiding the wasteful heat-up and cool-down cycles of the batch kilns.

  9. Carbonate–silicate cycle - Wikipedia

    en.wikipedia.org/wiki/Carbonate–silicate_cycle

    The inorganic cycle begins with the production of carbonic acid (H 2 CO 3) from rainwater and gaseous carbon dioxide. [6] Due to this process, normal rain has a pH of around 5.6. [ 7 ] Carbonic acid is a weak acid , but over long timescales, it can dissolve silicate rocks (as well as carbonate rocks).