Problem 121 - A Complete Resource Book in Chemistry for JEE Main

Question

The oxidation state of xenon atom in \(\mathrm{XeF}_{4}, \mathrm{HXeO}_{4}^{-}\), \(\mathrm{Na}_{4} \mathrm{XeO}_{6}\) are respectively (a) \(+4,+6,+8\) (b) \(+4,+6,+6\) (c) \(+4,+6,+7\) (d) \(+4,+5,+8\)

Step-by-Step Solution

Answer

The oxidation states are (a) \(+4, +6, +8\).

Step 1: Understanding Oxidation States

The oxidation state (OS) of an atom in a compound represents the charge that atom would have if the compound was composed of ions. For xenon compounds, we will determine the OS by considering the known oxidation states of the other elements in the compound and the overall charge of the compound.

Step 2: Calculating OS in \( \mathrm{XeF}_4 \)

Fluorine has a known oxidation state of \(-1\). In \( \mathrm{XeF}_4 \), there are 4 fluorine atoms. The total contribution from fluorine is \(-4\). To balance the charges to zero for a neutral molecule, xenon must have an oxidation state of \(+4\).

Step 3: Calculating OS in \( \mathrm{HXeO}_4^- \)

In \( \mathrm{HXeO}_4^- \), we have hydrogen with an OS of \(+1\), each oxygen with an OS of \(-2\) (for a total of \(-8\)). The ion has a net charge of \(-1\). Therefore, to balance this, xenon must have an OS of \(+6\): \(+6 + 1 - 8 = -1\).

Step 4: Calculating OS in \( \mathrm{Na}_4 \mathrm{XeO}_6 \)

Sodium has a known oxidation state of \(+1\). Thus, with 4 sodium atoms, the contribution is \(+4\). Each oxygen is \(-2\) (for a total of \(-12\) with 6 oxygens). Since the compound is neutral, xenon must have an OS of \(+8\): \(+4 + x - 12 = 0\), solving for \(x\) gives \(x = 8\).

Step 5: Conclusion

After calculating the oxidation states for xenon in each compound, we have \(+4\) for \( \mathrm{XeF}_4 \), \(+6\) for \( \mathrm{HXeO}_4^- \), and \(+8\) for \( \mathrm{Na}_4 \mathrm{XeO}_6 \). This matches option (a).

Key Concepts

Xenon Compounds

Xenon is a noble gas, usually characterized by its lack of chemical reactivity. However, under specific conditions, xenon can form compounds, often with elements like fluorine and oxygen. These are known as xenon compounds. They are interesting in the field of inorganic chemistry due to the unexpected ability of xenon to participate in chemical bonding. Xenon compounds, such as xenon hexafluoride (XeF_6) and xenon tetrafluoride (XeF_4), demonstrate that even the most inert elements can achieve versatile chemical states.

• These compounds are formed under rigorous conditions, typically involving high pressures or the presence of an electric field.
• The chemistry of xenon is facilitated by its ability to share electrons with other atoms, overcoming its natural inertness.

The formation of these compounds shows the rich tapestry of chemical behavior that can emerge under extreme conditions, making xenon a fascinating topic in inorganic chemistry. Nonetheless, the study of its compounds requires careful laboratory techniques due to their potential instability and the difficulty in handling noble gases.

Oxidation Number Calculation

Calculating the oxidation number, sometimes known as the oxidation state, is crucial for understanding the electronic structure of a compound. The oxidation number concept helps in depicting how electrons are distributed among the atoms in a compound. To calculate the oxidation state of xenon in any compound, consider the known oxidation states of other elements in the compound.

Steps to Calculate Oxidation Number:

• Identify the known oxidation states of each element in the compound. For instance, fluorine typically exhibits an oxidation state of -1, while oxygen is usually -2.
• Multiply the oxidation state of each element by the number of atoms of that element in the compound.
• Set up an equation that sets the sum of the product of oxidation states equal to the net charge of the compound.
• Solve for the unknown oxidation number, which is usually that of the central atom, like xenon.

This method helps to identify valency changes and predict the elemental behavior in compound formations. Being proficient in these calculations can provide better insights into the redox character and reactivity patterns of inorganic compounds.

Inorganic Chemistry

Inorganic chemistry is the study of inorganic compounds, which are not based on carbon-hydrogen bonds. This vast field encompasses varied subjects including

• arrangement and behavior of atoms in numerous compounds
• the methodologies for synthesis and reactivity of inorganic substances
• understanding the mechanisms that govern reactions involving metals and minerals

Focusing primarily on compounds like salts, metals, minerals, and gases, inorganic chemistry investigates chemical processes outside of hydrocarbons.

Key Areas of Inorganic Chemistry:

• Transition metals and their complex compounds.
• Role and behavior of non-metal elements like xenon.
• Studies related to metal-organic frameworks and their applications.

Understanding the fundamental principles of inorganic chemistry can elucidate the behavior of elements like xenon, which leads to the discovery and analysis of interesting compounds with novel properties. It involves extensive knowledge about the periodic table and the behavior of elements based on their electron configurations.