Question

One of the following oxides does not react with molecular oxygen: \(\mathrm{NO}, \mathrm{N}_{2} \mathrm{O}, \mathrm{SO}_{2}, \mathrm{SO}_{3}, \mathrm{P}_{4} \mathrm{O}_{6} .\) Based on oxidation numbers, which one is it? Explain.

Short answer

\(\mathrm{SO}_3\) does not react with molecular oxygen as it is in its maximum oxidation state.

Step-by-step solution

List Oxidation States

First, determine the oxidation state of each element in each oxide. - In \(\mathrm{NO}\), the oxidation state of \(\mathrm{N}\) is +2.- In \(\mathrm{N}_2\mathrm{O}\), the oxidation state of \(\mathrm{N}\) is +1.- In \(\mathrm{SO}_2\), the oxidation state of \(\mathrm{S}\) is +4.- In \(\mathrm{SO}_3\), the oxidation state of \(\mathrm{S}\) is +6.- In \(\mathrm{P}_4\mathrm{O}_6\), the oxidation state of \(\mathrm{P}\) is +3.

Consider Maximum Oxidation States

Elements have certain maximum oxidation states based on their placement in the periodic table. - The maximum oxidation state for \(\mathrm{N}\) is +5.- The maximum oxidation state for \(\mathrm{S}\) is +6.- The maximum oxidation state for \(\mathrm{P}\) is +5. Hence, check which oxides have not yet reached the maximum oxidation state.

Determine Reaction with Oxygen Possibility

Calculate whether any oxide can further increase its oxidation state by reacting with oxygen:- \(\mathrm{NO}\) can oxidize to \(\mathrm{NO}_2\), reaching \(\mathrm{N}\) oxidation state of +4.- \(\mathrm{N}_2\mathrm{O}\) can oxidize to another form still increasing the oxidation state.- \(\mathrm{SO}_2\) can oxidize further to \(\mathrm{SO}_3\), reaching the maximum \(\mathrm{S}\) oxidation state of +6.- \(\mathrm{SO}_3\) is already at the maximum oxidation state of sulfur, so it does not react further.- \(\mathrm{P}_4\mathrm{O}_6\) can oxidize to \(\mathrm{P}_4\mathrm{O}_{10}\), reaching \(\mathrm{P}\) oxidation state of +5.

Identify the Non-Reactive Oxide

Based on the analysis, identify which oxide will not react further with molecular oxygen because it already represents the highest oxidation state possible for its element. - \(\mathrm{SO}_3\) is at the highest oxidation state for sulfur and does not react further with oxygen.

Key concepts

Oxides

Oxides are compounds formed by the reaction of oxygen with other elements. They are classified into several types, but the most common are metallic oxides and non-metallic oxides. The nature of the element combined with oxygen dictates the properties of the oxide.
Some oxides can be acidic, basic, neutral, or amphoteric depending on their chemical behavior and the elements involved. The oxide's characteristics greatly affect its chemical reactions and potential interactions with other compounds or elements.
In this exercise, we encounter several oxides involving nitrogen, sulfur, and phosphorus. These oxides vary in how they interact with molecular oxygen based on their specific oxidation states.

Chemical Reactions

Chemical reactions involve the transformation of reactants into products, often involving the reorganization of electrons. In the context of oxides and oxidation states, chemical reactions can alter the oxidation state of elements to reach more stable configurations.
Here, the focus is on whether oxides react with molecular oxygen to form new compounds by changing oxidation states. Oxidation and reduction are key processes, where oxidation involves the loss of electrons (or increase in oxidation state), and reduction involves the gain of electrons (or decrease in oxidation state).

• For example, \( ext{NO}\) can further react with oxygen to form \( ext{NO}_2\), increasing the nitrogen oxidation state.
• Similarly, \( ext{SO}_2\) can oxidize to \( ext{SO}_3\).

However, when an oxide like \( ext{SO}_3\) is already at its maximum oxidation state, no further reaction with oxygen is possible.

Periodic Table

The periodic table is a valuable tool for understanding chemical properties and behaviors, including oxidation states. Elements are arranged based on increasing atomic number, and the table provides insights into the possible oxidation states of each element.
Groups and periods in the periodic table can reveal patterns in the maximum oxidation states for elements. For instance, nitrogen can typically achieve a maximum oxidation state of +5, sulfur +6, and phosphorus +5.
These maximum oxidation states help predict the capabilities of elements involved in forming oxides and engaging in further reactions. By knowing these limits, we can determine which oxides might react with additional oxygen molecules.

Maximum Oxidation State

The maximum oxidation state of an element is the highest positive charge it can achieve by losing electrons. This is often determined by the number of valence electrons an element can give up or share during chemical reactions.
In our exercise, we observed that many oxides can further oxidize until they hit this maximum state. Once an element in an oxide reaches its maximum oxidation state, it cannot undergo further oxidation, as seen with \( ext{SO}_3\) for sulfur.
Recognizing the maximum oxidation states is crucial for predicting chemical behavior and reaction potential, serving as a guiding principle in the analysis of chemical interactions and the stability of oxides.