Answer:
CaCO3 exoskeleton dissolves in acidic water
Explanation:
The increasing CO2 level makes the ocean water acidic and hence reduces the pH. In such acidic environment, marine organism that produce calcium carbonate shells or skeletons are negatively affected. Coral reefs and coralline algae abilities to produce skeleton also reduces.
Calcium carbonate dissolves in acid. Thus, the more acidic the ocean water is the faster and easier it is to dissolve the exoskeleton and shell of marine organisms made up of calcium carbonate
Elements combine to form chemical compounds that are often divided into two categories. Metals often react with nonmetals to form ionic compounds. These compounds are composed of positive and negative ions formed by adding or subtracting electrons from neutral atoms and molecules.
Answer: An atom that has gained an electron.
Explanation:
The number of protons in an atom cannot change except for some exceptional circumstances.
Cations (or metal ions) are formed when atoms lose electrons, as they want to form a complete outer electron shell to become as stable as possible.
For example, potassium is a 1+ ion, because it has one electron in its outer shell (and in group one). Therefore, to become more stable that electron is lost to become an ion or cation. As one electron is lost, the potassium cation charge is 1+ as the charge of an electron is 1-.