Consider the following statements about hydrogen peroxide: 1\. The extent of hydrogen bonding in \(\mathrm{H}_{2} \mathrm{O}_{2}\) is less than that in water. 2\. It is an important rocket fuel. 3\. It is used in cosmetics for bleaching hair. (a) Only 3 is correct (b) 2 and 3 are correct (c) 1 and 2 are correct (d) 1,2 and 3 are correct

Hydrogen bonding is a special type of dipole-dipole interaction that occurs between molecules. It involves a hydrogen atom that is attached to a highly electronegative element, such as oxygen, nitrogen, or fluorine. This bond occurs because the hydrogen atom, which has a partial positive charge, is attracted to the negative charge of another electronegative atom in a neighboring molecule.

To visualize the concept, let's take water (H₂O) as an example. The oxygen atom has a higher electronegativity compared to hydrogen, leading to a polar molecule with a bent structure. This polarity results in hydrogen bonds forming between the oxygen of one water molecule and the hydrogen of another, creating a cohesive and structured network.

In comparison, hydrogen peroxide (H₂O₂) also has a bent structure and is capable of hydrogen bonding, yet its structure is less favorable for extensive hydrogen bonding than water's structure. The oxygen-oxygen bond in hydrogen peroxide impedes the molecule from forming as strong a hydrogen-bonding network as seen in water. This is due to the repulsion between the lone pairs of electrons on the oxygen atoms and the overall molecular geometry, which affects the optimal orientation for hydrogen bonding. Thus, while hydrogen peroxide does engage in hydrogen bonding, the extent of these interactions is indeed less than that in water.

Hydrogen peroxide, with the chemical formula H₂O₂, plays an intriguing role as a rocket propellant. This application leverages the compound's ability to decompose rapidly under certain conditions, releasing a significant amount of oxygen in the process. When hydrogen peroxide is used as a rocket fuel, it often undergoes catalytic decomposition in the presence of a catalyst like manganese dioxide or silver.

The decomposition reaction of hydrogen peroxide can be represented as follows:
\[2 \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow 2 \mathrm{H}_{2} \mathrm{O} + \mathrm{O}_{2}\]
This reaction is highly exothermic, releasing not only oxygen but also heat, which is crucial for propulsion. The generated oxygen can then combust with other fuels to produce the expansive gases that thrust a rocket forward. Due to its high energy yield and relative simplicity of handling compared to other propellants, hydrogen peroxide is sometimes used in rocketry and jetpacks, making statement 2 correct.

In the realm of cosmetic chemistry, hydrogen peroxide is best known for its role as a bleaching agent. Its oxidizing properties make it effective for several applications, including hair and tooth bleaching. For hair, hydrogen peroxide acts by breaking down the natural pigments, known as melanin, which determines hair color.

When applied to hair, hydrogen peroxide can penetrate the hair shaft and react with the melanin. This reaction alters the chemical structure of the melanin, effectively reducing the pigments and lightening the hair color. The process of hair bleaching is often enhanced by alkaline conditions, which cause the hair shaft to swell, allowing better penetration of the hydrogen peroxide.

It's the controlled application and concentration that allow for different levels of bleaching, ranging from subtle highlights to a complete color change. Various concentrations of hydrogen peroxide are used, often in combination with other compounds, to achieve the desired effect without causing excessive damage to the hair. Apart from hair, lower concentrations of hydrogen peroxide are also used for skin treatments and teeth whitening products, thus confirming the accuracy of statement 3.