Understanding Acid Strengths: Nitric Acid vs. Phosphoric Acid

What are the differences in acid strengths between nitric acid and phosphoric acid?

Nitric Acid vs. Phosphoric Acid

Nitric acid and phosphoric acid are both important acids with different strengths in terms of acidity. Nitric acid (HNO3) is considered a stronger acid compared to phosphoric acid (H3PO4). The primary reason for this difference lies in their ability to ionize in water.

Nitric Acid:

Nitric acid is classified as a strong acid because it completely dissociates in water, releasing all of its protons (H+) to form hydronium ions (H3O+). The complete ionization of nitric acid results in a high concentration of hydronium ions in solution, making it a potent acid with a low pH.

Phosphoric Acid:

On the other hand, phosphoric acid is considered a weak acid due to its partial ionization in water. While phosphoric acid can donate protons to water molecules and partially dissociate into its constituent ions, it does not fully ionize like nitric acid. As a result, phosphoric acid has a less acidic nature compared to nitric acid.

Therefore, the stronger acid among nitric acid and phosphoric acid is nitric acid because of its full dissociation in water, leading to a higher concentration of hydronium ions and a lower pH.

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