CBSE Class 10 Answered

(a) Acids ionize in water to produce positively charged hydrogen ions (H⁺).
     Bases ionize in water to produce negatively charged hydroxide ions (OH^-).

(b) Hydrochloric acid will be a stronger acid than acetic acid because it completely ionizes in water to produce a large amount of hydrogen ions. On the other hand, acetic acid partially ionizes in water to produce only a small amount of hydrogen ions.

(c) The concentration of hydrogen ions decreases if an acid is diluted by adding more and more water to it.