CO2

[Sami Ryan 1G]

Why, when CO2 dissolves in water, does it lower the pH to make it more acidic? Aren't carbonates bases?

[Kayla Arellano 1K]

Why, when CO2 dissolves in water, does it lower the pH to make it more acidic? Aren't carbonates bases?

When CO2 reacts with water, the product is H2CO3 which is carbonic acid. H2CO3 can go on to further react with water to form HCO3- and H3O+ making the solution more acidic and lowering the pH.

[Charlie Gravereaux]

This is a two step process for CO2 to acidify water. First, CO2 will form H2CO3 with H2O, and from there, that H2CO3 (carbonic acid) can react further and form HCO3- and H3O+ (This process can also be repeated for HCO3- forming CO3-2 and H3O+). This will ultimately cause the solution to become acidic (a reason for acid rain).

[Amanda Dankberg 1B]

CO2 is mildly acidic and when it is put in water it forms H2CO3 which is an acid. It then can further dissacoiate into H3O+ and HCO3-

[Acharya Ranawat 3E]

CO2 reacts with water in order to form H2CO3. This dissociates (but partially) since it isn't a strong acid. This increases the H+ concentration.

[605778346]

H2CO3 is formed when CO2 reacts with water, which makes it more acidic.

[Debie_Morales1D]

Carbon dioxide can dissolve in water and reacts with it to form carbonic acid. Since the acid then dissociates into carbonate ions and hydrogen ions and eventually forms H30+ ions, it follows that an increase in CO2 will cause a decrease in pH because the solution is getting more acidic.

[Polo Morales 3C]

When it reacts with water, H2CO3 is formed. From there, the H2CO3 in water breaks down into HCO3- and H3O+, thereby lowering the pH of the rain and making it more acidic. Hope this helps!

[Robert Nguyen 14B-3E]

To give another example of a similar situation, SO3 is considered acidic because it combines with H2O to form H2SO4, which will donate 2 protons to the solution and thus turn the solution more acidic. This is the same situation with the CO2

[Robert Nguyen 14B-3E]

To give another example of a similar situation, SO3 is considered acidic because it combines with H2O to form H2SO4, which will donate 2 protons to the solution and thus turn the solution more acidic. This is the same situation with the CO2

[dahlia Faruque]

it is because when CO2 dissolves in water it creates carbonic acid which is a strong acid and so the solution becomes very acidic and as a result the pH is lowered.