Answer:
Solution Y is more acidic
Step-by-step explanation:
The pH value is an indicator of the concentration of hydrogen ions (H⁺) in an aqueous solution, and it is defined as:
pH= -log [H⁺]
⇒
Where [H⁺] is the concentration of H⁺. A solution with a higher concentration of H⁺ is more acidic, and a solution with a lower concentration of H⁺ is less acidic or basic.
As result, the lower the pH, the more the concentration of hydrogen ions ([H⁺]), and the aqueous solution is more acidic.
Solution Y has a lower pH value (7.5) than solution X (9.4). So, solution Y is more acidic.