Questions 2 a(i). Random motion Negligible volume Elastic collision (c) HOCl (hypochlorous acid) is considered acidic because it readily donates a hydrogen ion (H+) when dissolved in water, while NaOH (sodium hydroxide) is basic because it readily dissociates in water to produce hydroxide ions (OH-) which are responsible for a basic solution. Key points: HOCl: When HOCl dissolves in water, it can release a hydrogen ion (H+) making it an acid. NaOH: When NaOH dissolves in water, it readily separates into sodium (Na+) and hydroxide (OH-) ions, making it a base.