Question

17\. Classify the following compounds as acids or bases, weak or strong. (a) perchloric acid (b) cesium hydroxide (c) carbonic acid, \(\mathrm{H}_{2} \mathrm{CO}_{3}\) (d) ethylamine, \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{NH}_{2}\)

Short answer

Question: Classify the following compounds as strong or weak acids or bases: (a) Perchloric acid (HClO4), (b) Cesium hydroxide (CsOH), (c) Carbonic acid (H2CO3), and (d) Ethylamine (C2H5NH2). Answer: (a) Perchloric acid (HClO4) is a strong acid. (b) Cesium hydroxide (CsOH) is a strong base. (c) Carbonic acid (H2CO3) is a weak acid. (d) Ethylamine (C2H5NH2) is a weak base.

Step-by-step solution

(a) Perchloric acid (HClO4) classification

Perchloric acid (HClO4) is an acid because it has a hydrogen (H) atom that can be donated as a proton (H+) to another molecule. It is considered a strong acid since it ionizes almost completely (dissociates 100%) in water, releasing a high concentration of hydronium ions (H3O+) that result in a low pH (less than 7).

(b) Cesium hydroxide (CsOH) classification

Cesium hydroxide (CsOH) is a base because it contains a hydroxide (OH) group that can accept a proton (H+) from another molecule. It is considered a strong base as it ionizes almost completely (dissociates 100%) in water, releasing a high concentration of hydroxide ions (OH-) that result in a high pH (greater than 7).

(c) Carbonic acid (H2CO3) classification

Carbonic acid (H2CO3) is an acid because it has two hydrogen (H) atoms that can be donated as protons (H+) to other molecules. It is considered a weak acid as it does not ionize completely (dissociates less than 100%) in water, releasing a relatively low concentration of hydronium ions (H3O+), which results in a pH slightly lower than 7.

(d) Ethylamine (C2H5NH2) classification

Ethylamine (C2H5NH2) is a base because it contains an amine group (NH2) that can accept a proton (H+) from another molecule. It is considered a weak base as it does not ionize completely (dissociates less than 100%) in water, releasing a relatively low concentration of hydroxide ions (OH-) that would lead to a pH slightly greater than 7.