What is the mass of a cube of aluminum that is 3.0 cm on each edge? The density of aluminum is 2.7 g/cm3.

Do you know the formula? I can’t find it.

When dissociated into water, acids release hydrogen ions.

Whether the acids completely dissociates or not depend on whether the acid is strong or weak.
Strong acids (like HCl) completely dissociate in water while weak acids (like CH3COOH) partially dissociate in water.