Question

The correct method of finding the ph of a solution is to & why ?

Answer 1

Take the negative log of the concentration of hydrogen ions.

Explanation:

In chemistry, each letter in pH has a significant meaning:

p means to take the negative log of something (note that logarithms default to base `10` when a base is not specified)

H represents the concentration of hydrogen ions in the solution (note that pOH is also a possible way of measuring basicity and acidity based on the concentration of hydroxide ions)

pH `rarr` -log[`H^+`]

According Brønsted and Lowry, an acid is a substance that donates hydrogen ions when reacted with a base, which is why our method of measuring acidity, pH, measures the concentration of hydrogen ions (more hydrogen ions means more acidic). Since this measurement takes the negative log of the concentration, a lower pH means a more acidic solution. This system exists to explain levels of acidity in a simple way since `H^+` concentrations can be extremely small (down to almost `10^-13` M).