Peroxydisulfuric Acid: Structure, Preparation, Properties, Uses

Sample Questions

Ques. Can Peroxydisulfuric acid be prepared from chlorosulfonic acid? (3 Marks)

Ans. Yes, Peroxydisulfuric acid can also be prepared from chlorosulfuric acid. The reaction involves a hydrogen peroxide process. Usually, peroxydisulfuric acid is made by combining concentrated sulfuric acid with sodium persulfate. The solid form is substantially more difficult to produce and is used more frequently as a solution. The chemical equation for the preparation of Peroxydisulfuric acid is given as follows:

2CISO₃H + H₂O₂ → H₂S₂O₈ + 2HCl

Ques. How is the strength of oxidizing and reducing agents determined? (2 Marks)

Ans. The oxidizing agents' strength can be determined by their oxidation state, as in Cl+7, which cannot be further oxidized due to its valency. And Cl is in its most oxidized form. As a result, it can only be reduced; as a result, it now acts as a powerful oxidizing agent. Cl+5, on the other hand, acts as both a reducing and an oxidizing agent.

Ques. What happens when Peroxydisulfuric acid is dissolved in water? Explain the chemical reaction. Also mention the uses of Peroxydisulfuric Acid. (3 Marks)

Ans. When peroxydisulfuric acid dissolves in water, it produces sulfuric acid and hydrogen peroxide. The corresponding chemical equation is as follows:

H₂S₂O₈ + 2H₂O → H₂O₂ + 2H₂SO₄

Some of the common uses of Peroxydisulfuric Acid are mentioned below:

• The use of peroxydisulfuric acid and its salts as a source of hydrogen peroxide paved the door for large-scale sulphuric acid synthesis.
• Peroxydisulfuric acid can be used as a hypo eliminator in photography.
• It may also be used as a powerful oxidant, with the amount of oxidizing agent used varies depending on the desired reaction rate.

Ques. Mention some of the important differences between oxidizing and reducing agents? (3 Marks)

Ans. An oxidizing agent is a substance that seeks to remove electrons from the material with which it is interacting. It means oxidizing it or increasing its oxidation state. A reducing agent, on the other hand, seeks to add electrons to its reactant. 

It means, reducing it or reducing its oxidation state. In every situation, the opposite happens to the agent (an oxidizing agent can be reduced and gains either one or more electrons, where a reducing agent is oxidized and lose either one or more electrons).

Ques. What is water - an oxidizing or a reducing agent? Mention some examples of good oxidizing agents.

Ans. Water is neither a powerful oxidant nor a strong reducing agent, it can be either one depending on the substance with which it will react. One of the most common examples of an oxidising agent is acidified potassium dichromate (K2Cr2O7), which has an orange colour. 

Cr, which is in the oxidation state of +6, reduces to an oxidation state of +3, which is green in colour, and oxidises from SO2 to SO4- (+ 4 to +6) or with S (-2 to 0) when H2S or SO2 gas is passed through it. The presence of turbidity in the latter test suggests the development of Sulphur (S), which is present in colloid form.

Ques. How can we identify a good oxidizing agent? Explain with an example. (3 Marks)

Ans. In a chemical reaction, the oxidizing agent reduces itself while oxidizing the other element. It should have a strong tendency to gain electrons in order to display good oxidizing qualities, as we all know that oxidation is defined as the loss of electrons, while reduction is defined as the gain of electrons when it is reduced. 

As a result, it must gain electrons, with the oxidant's oxidizing propensity being determined by its electronegativity, and the ionization potential and electron affinity being high. For example, potassium permanganate is a good oxidizing agent, which we can demonstrate using a chemical process, as shown below:

MnO4- + 8H+ + 5e → Mn+2 + 4H2O

Ques. What makes the peroxydisulfuric acid different from other acids? Explain its characteristics. (3 Marks)

Ans. Peroxydisulfuric acid is a powerful peroxyacid oxidant. Peroxydisulfuric acid is one of the most potent peroxyacid oxidants. It is a colorless and odorless solid. Peroxydisulfuric acid is soluble in water and has a heavy atom count of 10. It is generated by oxidising oleum with ozone or hydrogen peroxide and is provided as an anhydride of peroxydisulfuric and sulphuric acid. 

Its salts, also known as persulfates, are used in industry as strong oxidizing agents. In a chemical reaction, the oxidizing agent reduces itself while oxidizing the other element. Peroxydisulfuric Acid is an inorganic substance with the formula H2S2O8. It may be made by dissolving potassium or ammonium persulfate in an acidic solution.

Ques. What happens when peroxydisulfuric acid reacts with silver nitrate in an aqueous medium. Also explain the preparation of peroxydisulfuric acid. (3 Marks)

Ans. When Peroxydisulfuric acid is placed in an aqueous medium along with silver nitrate, it reacts with silver nitrate to produce nitric acid, silver oxide, and sulphuric acid. The chemical equation for this reaction can be given as follows:

H₂S₂O₈ + 2AgNO₃ + 2H₂O → Ag₂O₂ + 2H₂SO₄+ 2HNO₃

The sodium persulfate compound can be used to make peroxydisulfuric acid by mixing concentrated sulfuric acid with it. Also, chlorosulfonic acid can be used to make this acid, which includes a hydrogen peroxide process. The solid form is substantially more difficult to obtain and is used more frequently as a solution.