Question

One liter of a solution ph 9 has how many more hydroxide ions (oh-) than 1 l of a solution of ph 4?

Answer 1

A solution with a pH of 9 has 100,000 times more hydroxide ions than a solution with a pH of 4 due to the corresponding pOH values and hydroxide ion concentrations based on the relationship between pH and pOH.

Step-by-step explanation:

The student has asked about the difference in the number of hydroxide ions between a solution with a pH of 9 and another with a pH of 4. Using the relationship PH + pOH = 14, we can find the pOH.

For the pH 9 solution, the pOH would be 5 (14 - 9), which corresponds to a [OH-] of 1.0 × 10-5 M. For the pH 4 solution, the pOH would be 10 (14 - 4), corresponding to a [OH-] of 1.0 × 10-10 M. Hence, the pH 9 solution has 1.0 × 10-5 M of OH-, which is 100,000 times greater than the 1.0 × 10-10 M OH- in the pH 4 solution.

Answer 2

100,000 times more. The rule is that the product of the concentration of (H+) and (OH-) in molars is always 10^-14 (if it is more, they combine and produce simple water which brings the product back down to this number again. If it is less, water molecules will split to bring the product back up to equilibrium).
pH 9 means (H+) is 10^-9 molar. But that means (OH-) is 10^-5 at the same time.
pH 4 means (H+) is 10^-4 molar. But that means (OH-) is 10^-10 at the same time.
10^-5 / 10^-10 = 10^5 or 100,000 times more.