Question

Carbon dioxide dissolves in water to form carbonic acid.
a.) True
b.) False

Answer 1

Hint: In this question we should know that marine plants use dissolved carbon dioxide, sunlight and water to make carbohydrates through the process of photosynthesis. And also when we drink soda water, the taste of it is an effect of the dissolved carbon dioxide .And we should focus that not all the carbon dioxide present gets dissolved in ocean water.

Complete step-by-step answer:
We can answer this question by taking the example of marine life. We should know that dissolved oxygen and carbon dioxide are vital for marine life. Marine plants use dissolved carbon dioxide, sunlight and water to make carbohydrates through the process of photosynthesis. This process releases oxygen into the water. All marine organisms use oxygen for respiration, which releases energy from carbohydrates and has carbon dioxide and water as by-products. Marine animals with gills, such as fish, use these organs to extract oxygen from the seawater.
It is important to note that Carbon dioxide is one of the most important gases that dissolve in the ocean. Some of it stays as dissolved gas, but most reacts with the water to form carbonic acid or reacts with carbonates already in the water to form bicarbonates. This removes dissolved carbon dioxide from the water. Carbon dioxide is soluble in water, in which it reversibly forms \[{{H}_{2}}C{{O}_{3}}\] (carbonic acid), which is a weak acid since its ionization in water is incomplete.
\[C{{O}_{2}}\text{ }+\text{ }{{H}_{2}}O\rightleftharpoons {{H}_{2}}C{{O}_{3}}\]
So, from the above discussion we now know that carbon dioxide dissolves in water to form carbonic acid. We should know that the ocean acts as an enormous carbon sink, and have taken up about a third of Carbon dioxide. And one important factor that we should focus on is that gas solubility decreases as the temperature of water increases and therefore the rate of uptake from the atmosphere decreases as ocean temperatures rise. So, now we know that carbon dioxide dissolves in water to form carbon dioxide. So, the statement provided in the question is a true statement.

Note: We should here note that the increase in concentration of carbon dioxide in the atmosphere, increases the uptake of carbon dioxide into the oceans which causes a measurable decrease in the pH of the oceans, which is referred to as ocean acidification. This reduction in pH affects biological systems in the oceans, primarily oceanic calcifying organisms. These effects span the food chain from autotrophs to heterotrophs and include organisms such as coccolithophores, corals, foraminifera, echinoderms, crustaceans and mollusks.