What happens to the PH of seawater when calcium carbonate materials dissolve in seawater?

Answer 1

The Ph level of seawater decreases when Carbon Dioxide is introduced. The basic chemical equation for this is:

CO2(aq) + H2O(l) <--> H2CO3(aq)

H2CO3(aq), Carbonic acid, is a very weak acid that will easy dissociate into H+ and HCO3-. This means that only about 1% of the dissolved CO2 actually affects the pH of seawater as an acid.

However, the increased acidity produced by the addition of CO2 has many negative consequences to the ocean environment. When carbonic acid dissociates, it produces CO32-, the carbonate ion. This ion can react with many dissolved metal ions, such as Ca2+ and Mg2+, forming precipitates such as limestone and dolomite on the ocean floor. In addition, excessively acidic surface seawater can also dissolve some types of rocks, such as limestone, weakening the stone and creating many holes. Both of these reactions affect ocean life by very quickly and drastically changing the composition of the abiotic environment.

Answer 2

The pH of seawater increases when calcium carbonate materials dissolve in it. This is because the process of dissolving calcium carbonate consumes carbon dioxide, leading to a decrease in the concentration of carbonic acid and an increase in pH.

Answer 3

Calcium and carbonate ions interact.

Answer 4

Increases