Question

question 1
what happens to the concentration of hydrogen ions in a solution when acids dissolve?

increases

decreases

remains the same

none of these

question 2
__________ are substances that increase the concentration of hydroxide ions in a solution.

acids

bases

salts

none of these

Explanation:

• For Question 1: According to the Arrhenius theory, acids dissociate in water to produce hydrogen ions ($H^{+}$). So, when acids dissolve, the concentration of hydrogen ions in the solution increases.
• For Question 2: Bases, as per the Arrhenius theory, dissociate in water to produce hydroxide ions ($OH^{-}$). So, bases are substances that increase the concentration of hydroxide ions in a solution.

Answer:

• Question 1: Increases
• Question 2: Bases