Question

The ability of water to act as an agent of chemical weathering is commonly enhanced by the addition of CO2 from __________ to the water to form carbonic acid.

1. the atmosphere
2. soils
3. all of the above
4. none of the above

Answer 1

The ability of water to contribute to chemical weathering by forming carbonic acid is enhanced by the addition of carbon dioxide from both the atmosphere and soils, making 'all of the above' the correct answer.

Step-by-step explanation:

The ability of water to act as an agent of chemical weathering is commonly enhanced by the addition of CO2 from all of the above to the water to form carbonic acid.

Carbon dioxide (CO2) contributes to chemical weathering when it dissolves in water, forming carbonic acid. This acid is a weak acid capable of breaking down rocks and minerals, a process important in the formation of soil and the releasing of minerals to the environment. This CO2 can originate from the atmosphere, where it is a major gas released by various processes including respiration, decomposition, and the combustion of fossil fuels. CO2 is also produced in the soil by the decomposition of organic matter and root respiration, and this CO2 can be dissolved in water that percolates through the soil. Rainwater naturally contains dissolved CO2 from the atmosphere, enhancing its capacity for chemical weathering when it comes into contact with rocks. Over time, chemical weathering can lead to significant changes in the landscape and the carbon cycle, due to the reactions of carbonic acid with minerals to form bicarbonate and carbonate ions.