Question

Name two acids used in the pH of pure water

Answer 1

The pH of pure water can be altered by adding acids or alkalis, according to our requirements.

• pH of pure water is 7. Though dissociation of water molecules produces $H^{+}$ ions, it does not turn acidic as these ions are taken up by other water molecules to form a coordinate compound $H_{3}O$.
• In order to make water acidic, we need to increase $H^{+}$ ion concentration above saturation. By adding acids such as phosphoric acid ($H_{3}PO_{4}$) or acetic acid ($CH_{3}COOH$) the concentration of hydrogen ions increases due to dissociation of the acid in water.
• Increase in the concentration of $H^{+}$ in water decreases its pH, making it acidic.

Answer 2

Two acids used in the pH of pure water are phosphoric acid $H3PO4$$H3PO4$ and acetic acid $CH3COOH$

Explanation:

• Pure Water is water $H2O$ which is having a pH of $7$
• This water is known as distilled water. It is considered as neutral as it is neither acidic nor basic.
• The pH of pure water can be changed by the addition of some acids and alkalis.
• Dissociation of water molecules produces ions, which do not turn acidic as these ions are taken by another water molecule to form a coordinate bond.
• We can water acidic by increasing the ion concentration.
• For this Phosphoric acids and Acetic acid can be added which will help in increasing the hydrogen ion concentration.
• This happens when the concentration of hydrogen ions increases as the dissociation of acid in water takes place.
• The increase in the hydrogen ion concentration will increase the acidity and decrease the pH.