Question

Peroxodisulphate, on hydrolysis yields (a) water (b) dihydrogen (c) hydrogen peroxide (d) deuterium.

Short answer

Peroxodisulphate on hydrolysis yields hydrogen peroxide (H2O2).

Step-by-step solution

Understanding Hydrolysis of Peroxodisulphate

Hydrolysis is a reaction involving the breaking of a bond in a molecule using water. Peroxodisulphate (also known as peroxodisulfate) is a compound with the formula S2O8^2-. When it undergoes hydrolysis, it reacts with water to produce sulfate ions and a particular kind of oxygen species.

Identifying the Products of Hydrolysis

In the hydrolysis of peroxodisulphate, the O-O bond within the S2O8^2- ion is broken and each oxygen atom binds with a hydrogen atom from water, forming hydrogen peroxide (H2O2). This process does not yield water, dihydrogen, or deuterium directly as the main product.

Determining the Correct Answer

Since hydrogen peroxide is formed during the hydrolysis of peroxodisulphate because it involves the combination of peroxodisulphate with hydrogen atoms from water, option (c) hydrogen peroxide is the correct answer.

Key concepts

Chemical Reactions

A chemical reaction is a process in which one or more substances, the reactants, are converted into one or more different substances, the products. These transformations are the core of chemistry and can occur in various forms, such as synthesis, decomposition, and hydrolysis, which is relevant to our current discussion. Hydrolysis specifically refers to a reaction where a water molecule is used to break chemical bonds.

In the case of the hydrolysis of peroxodisulphate, the reaction entails the breaking of the O-O bond of the S2O8^2- ion. It's crucial to note that, unlike combustion reactions that produce water and dioxide, hydrolysis reactions use water to break down compounds. This subtle difference is often a point of confusion but is key in correctly understanding chemical reactions such as the one given in the exercise. Through careful analysis of the reaction process and the substances involved, we can determine the correct products formed.

Inorganic Chemistry

Inorganic chemistry is the branch of chemistry concerned with the properties and behavior of inorganic compounds, which include metals, minerals, and organometallic compounds. In this area of chemistry, there is a vast array of substances we encounter, one of which is oxyanions.

Oxyanions are negative ions containing oxygen. They are often formed by the combination of an element with oxygen and one or more additional elements. Peroxodisulphate is an example of an oxyanion, where sulfur is the central element and is surrounded by oxygen atoms, forming the polyatomic ion S2O8^2-. Understanding the structure and reactivity of oxyanions in solution is essential, and hydrolysis reactions are a common way that the properties of these ions are explored and understood in the context of inorganic chemistry.

Oxyanions

Oxyanions play a pivotal role in both natural processes and industrial applications. These ions, as mentioned earlier, consist of an element bonded to one or more oxygen atoms. The peroxodisulphate ion is one such oxyanion where sulfur is bonded to multiple oxygen atoms, creating the S2O8^2- ion. The various oxygens exhibit different levels of reactivity based on their chemical environment and bonding.

In hydrolysis reactions, peroxodisulphate is an interesting case because it involves the breaking of an oxygen-oxygen bond, not commonly seen in simpler oxyanions like sulfate (SO4^2-). Understanding the behavior of peroxodisulphate in hydrolysis is key to grasping the broader concepts of how oxyanions behave chemically. Importantly, it highlights how variations in structure among oxyanions lead to diverse chemical reactivity patterns, connecting back to overarching principles in inorganic chemistry.