Phosphoric Acid vs Dihydrogen Phosphate: Exploring the Differences

What can you tell about the relative concentrations of phosphoric acid and dihydrogen phosphate based on their pH levels?

Which one is more acidic - Phosphoric Acid or Dihydrogen Phosphate?

Answer:

Phosphoric Acid is more acidic than Dihydrogen Phosphate based on their pH levels.

Phosphoric acid and dihydrogen phosphate are both important chemical compounds with varying levels of acidity. Phosphoric acid, with a pH of 2.42, is considered a stronger acid compared to dihydrogen phosphate, which has a pH of 6.86.

Phosphoric acid contains 4 atoms of phosphorus and 3 atoms of hydrogen, while dihydrogen phosphate is moderately acidic and consists of hydrogen ions and phosphate ions in its solution. This difference in composition contributes to the variance in their pH levels.

One key factor influencing the acidity of these compounds is the dissociation of hydrogen ions. In the case of phosphoric acid, hydrogen ions dissociate more readily compared to dihydrogen phosphate. This is due to the chemical structure and composition of each compound.

Additionally, dihydrogen phosphate, being a nonmetal phosphate, tends to partially dissociate in its ion solution, leading to a higher pH compared to phosphoric acid. The presence of more oxygen molecules in dihydrogen phosphate limits the dissociation process, making it less acidic than phosphoric acid.

Overall, the relative concentrations of phosphoric acid and dihydrogen phosphate can be determined based on their pH levels, with phosphoric acid exhibiting stronger acidic properties compared to dihydrogen phosphate.