Question

Write a balanced equation for what happens when gaseous \(\mathrm{NH}_{3}\) is dissolved in water.

Short answer

The balanced equation for the dissolution of gaseous ammonia in water is: \(\mathrm{NH}_{3} + \mathrm{H}_{2}\mathrm{O} \rightarrow \mathrm{NH}_{4}^{+} + \mathrm{OH}^{-}\)

Step-by-step solution

Write the reactants and products

Write down the reactants on the left side of the equation and the products on the right side of the equation with an arrow in between, representing the conversion of reactants to products. $$\mathrm{NH}_{3} + \mathrm{H}_{2}\mathrm{O} \rightarrow \mathrm{NH}_{4}^{+} + \mathrm{OH}^{-}$$

Balance the equation

Count the atoms of each element on both sides of the equation and compare them. If they are not equal for any element, adjust the coefficients so that they are equal. Let's first list the atoms on both sides of the equation: - Reactants: 1 nitrogen, 3 hydrogens (in \(\mathrm{NH}_{3}\)) + 2 hydrogens and 1 oxygen (in \(\mathrm{H}_{2}\mathrm{O}\)) - Products: 1 nitrogen, 4 hydrogens (in \(\mathrm{NH}_{4}^{+}\)) + 1 hydrogen and 1 oxygen (in \(\mathrm{OH}^{-}\)) We can see that there are equal numbers of nitrogen and oxygen atoms on both sides, and the total number of hydrogen atoms is 5 on both sides (3 from NH3 and 2 from H2O on the reactants side, 4 from NH4+ and 1 from OH- on the products side). Since the equation is already balanced, no further adjustments are needed.

Final Balanced Equation

The balanced equation for the dissolution of gaseous ammonia in water is: $$(1)\:\mathrm{NH}_{3} + (1)\:\mathrm{H}_{2}\mathrm{O} \rightarrow (1)\:\mathrm{NH}_{4}^{+} + (1)\:\mathrm{OH}^{-}$$

Key concepts

Chemical Reactions

Understanding chemical reactions is essential for anyone studying chemistry. In the realm of science, a chemical reaction refers to the process by which substances, known as reactants, transform into new substances, which we call products. This transformation involves breaking and forming chemical bonds, leading to changes in the composition and properties of the involved reactants.

For example, when gaseous ammonia ((NH_3)), a compound consisting of nitrogen and hydrogen, is exposed to water (H_2O), a chemical reaction occurs through a process called dissolution. Here, gaseous ammonia is dissolved in water, generating ammonium ions ((NH_4^+)) and hydroxide ions ((OH^-)), which are the products of this reaction. It's like a dance of atoms where they switch partners to create something new, resulting in an observable change that can be described by a balanced chemical equation.

Dissolution of Gases

One of the fascinating interactions in chemistry is the dissolution of gases in liquids. Dissolution can be thought of as a gas 'vanishing' into a liquid, creating a homogenous mixture, or solution. This process can be influenced by factors such as temperature, pressure, and the nature of the gas and liquid involved. In our specific example, ammonia gas dissolves in water, a phenomenon commonly observed in various environmental and industrial processes.

Dissolution is a physical process where the molecules of a gas are interspersed among the molecules of a liquid. In the case of gaseous ammonia, the dissolution involves a reaction, as the ammonia gas reacts with water molecules, leading to the formation of ammonium and hydroxide ions. The solubility of gases like (NH_3) in water is a crucial concept in fields like environmental science, where the absorption of toxic gases into rainwater can have significant implications.

Stoichiometry

Stoichiometry is a branch of chemistry that deals with the quantitative relationships between the substances involved in chemical reactions. It allows chemists to predict the amounts of reactants needed and the quantity of products formed in a chemical reaction.

In simple terms, it's like a recipe that tells us how much of each ingredient we need to make our final product. When we balance a chemical equation, we're applying the principles of stoichiometry to ensure that the atoms of each element are conserved. In the given exercise, we balanced the equation for the dissolution of (NH_3) gas in water, ensuring that the count of nitrogen, hydrogen, and oxygen atoms are the same on both the reactant and product sides. This precision guarantees that our 'chemical recipe' reflects what actually happens in the reaction, allowing us to accurately predict the outcome of the chemical change and understand the conversion ratios of reactants to products.