Question

A scientist observes that after mixing a solid powder into water, the pH of the newly formed solution is 2.7. What can he infer from this observation?

The solution contains an indicator that has a pH of 2.7.
The solid powder contained hydrogen ions.
The pH indicator was used incorrectly.
The powder increased the hydrogen ion concentration of the solution.

Answer 1

The powder increased the hydrogen ion concentration in the water

Step-by-step explanation:

The ion that is responsible for acidity is the hydrogen ion. This is why all acids have the hydrogen ion in them. Examples are HCl, HBr, HNO3, H2SO4. So a solution with a higher concentrations of hydrogen ions in solution will be more acidic than one with less hydrogen ions in solution, So clearly in this case, the reason this powder would change the pH of water from 7 to 2.7 would be because there has been an increase in acidity of the solution or an increase in the concentration of hydrogen ions

Answer 2

I think the last option is the correct answer. The powder increased the hydrogen ion concentration of the solution. The said statement is the inference we can make from the situation. pH is the measure of hydrogen ions in a solution. The powder when added in the solution most likely dissociates into ions, especially hydrogen ions, thus decreasing the pH.