Find the pH of a 0.20 mol/L NaNO3 solution.

What is the pH of a 0.20 mol/L NaNO3 solution?

The pH of a solution is a measure of its acidity or alkalinity. In this case, we are given that we have a 0.20 mol/L solution of sodium nitrate, NaNO3, with a pH of 8.57. This means that the solution is basic since a pH above 7 indicates alkalinity.

Explanation:

pH scale: The pH scale measures the concentration of hydrogen ions in a solution. A pH of 7 is considered neutral, below 7 is acidic, and above 7 is basic or alkaline.

Sodium nitrate, NaNO3: When sodium nitrate dissolves in water, it dissociates into sodium ions (Na+) and nitrate ions (NO3-). Since neither sodium ions nor nitrate ions react with water to form or consume hydrogen ions, the solution remains neutral. Therefore, the pH of a sodium nitrate solution is close to 7.

pH of 8.57: The fact that the solution has a pH of 8.57 indicates that something else is affecting the pH. In this case, it could be due to the hydrolysis of the nitrate ion (NO3-) in the water, leading to the formation of hydroxide ions (OH-) and increasing the pH of the solution.

Calculating pH: If you want to calculate the exact pH of a 0.20 mol/L NaNO3 solution, you would need to consider the dissociation of the nitrate ion and the hydrolysis reaction that occurs in water. By taking into account the equilibrium constants for these reactions, you can determine the pH value more accurately.