Problem 81 - Chemistry The Central Science

Question

Write a balanced equation for the reaction of each of the following compounds with water: (a) \(\mathrm{SO}_{2}(g)\) (b) \(\mathrm{Cl}_{2} \mathrm{O}_{7}(g),(\mathrm{c})\) \(\mathrm{Na}_{2} \mathrm{O}_{2}(s),(\mathbf{d}) \mathrm{BaC}_{2}(s)\) (e) \(\mathrm{RbO}_{2}(s),\) (f) \(\mathrm{Mg}_{3} \mathrm{~N}_{2}(s),(\mathrm{g}) \mathrm{NaH}(s)\)

Step-by-Step Solution

Answer

The short versions of the balanced equations for each reaction are: (a) \(\mathrm{SO}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(l) \rightarrow \mathrm{H}_{2}\mathrm{SO}_{3}(aq)\) (b) \(\mathrm{Cl}_{2}\mathrm{O}_{7}(g) + 4\mathrm{H}_{2}\mathrm{O}(l) \rightarrow 2\mathrm{HClO}_{4}(aq)\) (c) \(\mathrm{Na}_{2}\mathrm{O}_{2}(s) + 2\mathrm{H}_{2}\mathrm{O}(l) \rightarrow 2\mathrm{NaOH}(aq) + \mathrm{O}_{2}(g)\) (d) \(\mathrm{BaC}_{2}(s) + 2\mathrm{H}_{2}\mathrm{O}(l) \rightarrow \mathrm{Ba(OH)}_{2}(aq) + \mathrm{C}_{2}\mathrm{H}_{2}(g)\) (e) \(\mathrm{RbO}_{2}(s) + \mathrm{H}_{2}\mathrm{O}(l) \rightarrow 2\mathrm{RbOH}(aq) + \mathrm{O}_{2}(g)\) (f) \(\mathrm{Mg}_{3}\mathrm{N}_{2}(s) + 6\mathrm{H}_{2}\mathrm{O}(l) \rightarrow 3\mathrm{Mg(OH)}_{2}(aq) + 2\mathrm{NH}_{3}(g)\) (g) \(\mathrm{NaH}(s) + \mathrm{H}_{2}\mathrm{O}(l) \rightarrow \mathrm{NaOH}(aq) + \mathrm{H}_{2}(g)\)

Step 1: Identify the reaction products

The compound \(\mathrm{SO}_{2}\) reacts with water to form sulfurous acid, \(\mathrm{H}_{2}\mathrm{SO}_{3}\).

Step 2: Balance the equation

The balanced equation for the reaction of \(\mathrm{SO}_{2}\) and water is: \(\mathrm{SO}_{2}(g) + \mathrm{H}_{2}\mathrm{O}(l) \rightarrow \mathrm{H}_{2}\mathrm{SO}_{3}(aq)\) (b) Reaction of \(\mathrm{Cl}_{2}\mathrm{O}_{7}(g)\) with water

Step 1: Identify the reaction products

The compound \(\mathrm{Cl}_{2}\mathrm{O}_{7}\) reacts with water to form perchloric acid, \(\mathrm{HClO}_{4}\).

Step 2: Balance the equation

The balanced equation for the reaction of \(\mathrm{Cl}_{2}\mathrm{O}_{7}\) and water is: \(\mathrm{Cl}_{2}\mathrm{O}_{7}(g) + 4\mathrm{H}_{2}\mathrm{O}(l) \rightarrow 2\mathrm{HClO}_{4}(aq)\) (c) Reaction of \(\mathrm{Na}_{2}\mathrm{O}_{2}(s)\) with water

Step 1: Identify the reaction products

The compound \(\mathrm{Na}_{2}\mathrm{O}_{2}\) reacts with water to form sodium hydroxide, \(\mathrm{NaOH}\), and oxygen gas, \(\mathrm{O}_{2}\).

Step 2: Balance the equation

The balanced equation for the reaction of \(\mathrm{Na}_{2}\mathrm{O}_{2}\) and water is: \(\mathrm{Na}_{2}\mathrm{O}_{2}(s) + 2\mathrm{H}_{2}\mathrm{O}(l) \rightarrow 2\mathrm{NaOH}(aq) + \mathrm{O}_{2}(g)\) (d) Reaction of \(\mathrm{BaC}_{2}(s)\) with water

Step 1: Identify the reaction products

The compound \(\mathrm{BaC}_{2}\) reacts with water to form barium hydroxide, \(\mathrm{Ba(OH)}_{2}\) and acetylene gas, \(\mathrm{C}_{2}\mathrm{H}_{2}\).

Step 2: Balance the equation

The balanced equation for the reaction of \(\mathrm{BaC}_{2}\) and water is: \(\mathrm{BaC}_{2}(s) + 2\mathrm{H}_{2}\mathrm{O}(l) \rightarrow \mathrm{Ba(OH)}_{2}(aq) + \mathrm{C}_{2}\mathrm{H}_{2}(g)\) (e) Reaction of \(\mathrm{RbO}_{2}(s)\) with water

Step 1: Identify the reaction products

The compound \(\mathrm{RbO}_{2}\) reacts with water to form rubidium hydroxide, \(\mathrm{RbOH}\)-, and oxygen gas, \(\mathrm{O}_{2}\).

Step 2: Balance the equation

The balanced equation for the reaction of \(\mathrm{RbO}_{2}\) and water is: \(\mathrm{RbO}_{2}(s) + \mathrm{H}_{2}\mathrm{O}(l) \rightarrow 2\mathrm{RbOH}(aq) + \mathrm{O}_{2}(g)\) (f) Reaction of \(\mathrm{Mg}_{3}\mathrm{N}_{2}(s)\) with water

Step 1: Identify the reaction products

The compound \(\mathrm{Mg}_{3}\mathrm{N}_{2}\) reacts with water to form magnesium hydroxide, \(\mathrm{Mg(OH)}_{2}\), and ammonia gas, \(\mathrm{NH}_{3}\).

Step 2: Balance the equation

The balanced equation for the reaction of \(\mathrm{Mg}_{3}\mathrm{N}_{2}\) and water is: \(\mathrm{Mg}_{3}\mathrm{N}_{2}(s) + 6\mathrm{H}_{2}\mathrm{O}(l) \rightarrow 3\mathrm{Mg(OH)}_{2}(aq) + 2\mathrm{NH}_{3}(g)\) (g) Reaction of \(\mathrm{NaH}(s)\) with water

Step 1: Identify the reaction products

The compound \(\mathrm{NaH}\) reacts with water to form sodium hydroxide, \(\mathrm{NaOH}\), and hydrogen gas, \(\mathrm{H}_{2}\).

Step 2: Balance the equation

The balanced equation for the reaction of \(\mathrm{NaH}\) and water is: \(\mathrm{NaH}(s) + \mathrm{H}_{2}\mathrm{O}(l) \rightarrow \mathrm{NaOH}(aq) + \mathrm{H}_{2}(g)\)

Key Concepts

Chemical Reactions with Water

In chemistry, a reaction with water is often referred to as a hydrolysis reaction. This occurs when a chemical compound combines with water, leading to a chemical change. Let's explore a few reactions that illustrate this principle. For instance, sulfur dioxide (SO_2) reacts with water to form sulfurous acid (H_2SO_3). Similarly, dichlorine heptoxide (Cl_2O_7) reacts with water to yield perchloric acid (HClO_4). Water acts as a reactant that alters the original compound, leading to the formation of different products. For metal oxides like sodium peroxide (Na_2O_2) and rubidium superoxide (RbO_2), their interaction with water results in hydroxides and oxygen gas depending on their specific chemistry.
It’s important to always consider the properties of the original compounds and the expected reaction products. Commonly, non-metal oxides react with water to form acids, while metal oxides create bases. Balancing such equations ensures that the number of each type of atom is equal on both sides of the equation, preserving the mass and charge.

Oxidation States

Oxidation states, also known as oxidation numbers, provide insight into the electron transfer processes occurring during chemical reactions. They illustrate how electrons are distributed in chemical compounds and influence their reactivity.
For instance, in (SO_2) reacting with water, the sulfur atom holds an oxidation state of +4. Upon forming H_2SO_3, the oxidation state's assessment confirms its consistency across reactants and products. In the case of Cl_2O_7 transformed to HClO_4 with water, chlorine's oxidation state of +7 remains unchanged post-reaction. These states offer clarity in frameworks like redox reactions, showing electron exchange.
Applying oxidation states in balancing reactions ensures a detailed understanding of electron movement, which is crucial in both acid-base and redox reactions, allowing chemists to predict reaction outcomes accurately.

Acid-Base Reactions

Acid-base reactions are fundamental in understanding chemical processes, particularly those that involve protons (H^+ ions) and hydroxide ions (OH^-). When compounds such as Na_2O_2 or RbO_2 interact with water, they often produce hydroxides - a hallmark of base formation. The converse can occur with nonmetal oxides, which typically generate acids when dissolved in water.
Consider that acids are proton donors and bases are proton acceptors; their interactions with water are crucial in many chemical phenomena. NaH, a strong base, generates NaOH by capturing the aqueous protons upon hydrolysis. Such reactions are key to various biochemical processes and industrial applications, influencing the pH and the chemical properties of solutions. Furthermore, understanding acidity and basicity through these reactions provides insights into the behavior of substances in solution and how they might react under different conditions.

Inorganic Chemistry Concepts

Inorganic chemistry studies substances that aren't based on carbon-hydrogen bonds, including metals, minerals, and organometallics. Reactions with water show how these substances behave in the environment and under various conditions. Consider that compounds like BaC_2 with water generate Ba(OH)_2 and C_2H_2, displaying typical inorganic reactions where carbides interact with water to produce acetylene.
In inorganic chemistry, knowledge of how different elements and compounds react with water informs everything from mineral extraction techniques to environmental science. Understanding these processes helps predict how compounds will behave, whether constructing new materials or studying natural elemental cycles. This knowledge is essential for chemists as they develop new compounds or assess the impacts of existing ones, ensuring advancements in both technology and environmental management.