Question

Write the balanced chemical equation that represents the equilibrium between HF(aq) as reactants and \(\mathrm{H}^{+}(\mathrm{aq})\) and \(\mathrm{F}^{-}\) (aq) as products.

Short answer

The balanced equation is \( \mathrm{HF(aq)} \rightleftharpoons \mathrm{H}^{+}(\mathrm{aq}) + \mathrm{F}^{-}(\mathrm{aq}) \).

Step-by-step solution

Identify Reactants and Products

We start by identifying the reactants and the products in the chemical reaction. The reactant given is HF(aq) and the products are \( \mathrm{H}^{+}(\mathrm{aq}) \) and \( \mathrm{F}^{-}(\mathrm{aq}) \). This indicates that in this equilibrium, HF dissociates into its ions.

Write the Unbalanced Chemical Equation

The next step is to write the possible unbalanced chemical equation using the identified reactants and products. This is represented as follows: \[ \mathrm{HF(aq)} \rightleftharpoons \mathrm{H}^{+}(\mathrm{aq}) + \mathrm{F}^{-}(\mathrm{aq}) \].

Balance the Chemical Equation

In this step, we check if the chemical equation is balanced. Since the equation shows the dissociation of one molecule of HF into one \( \mathrm{H}^{+} \) and one \( \mathrm{F}^{-} \), the equation is already balanced. The number of atoms of each element and the charge is conserved across the equation.

Key concepts

Chemical Equations

Chemical equations are symbolic representations of chemical reactions. They allow us to see which substances are involved and how they interact. In a chemical equation, the reactants are typically shown on the left side while the products appear on the right. These components are separated by an arrow that signifies the direction of the reaction.
In the case of reversible reactions, such as the dissociation of hydrofluoric acid (HF) into hydrogen ions \(\text{H}^{+}\) and fluoride ions \(\text{F}^{-}\), a double arrow (↔) is used. This symbol indicates that the reaction can proceed in both directions, reaching a state of equilibrium where the concentrations of reactants and products remain constant.
Understanding chemical equations involves recognizing the chemical formulas for the reactants and products, the states of matter (indicated by symbols like (s), (l), (g), and (aq) for aqueous solutions), and the stoichiometry, which tells us the proportions of substances involved. This foundational knowledge is crucial for further study in chemistry.

Dissociation Reactions

Dissociation reactions describe the process by which a compound separates into its ions when dissolved in water. These types of reactions are common in acids, bases, and salts. When HF dissolves in water, the molecules dissociate into \(\text{H}^{+}\) and \(\text{F}^{-}\) ions.
The ability of a substance to dissociate in water often defines its strength as an acid or a base. HF is a weak acid, meaning that it does not completely dissociate in solution. Only a small fraction of HF molecules break into ions. This incomplete dissociation results in an equilibrium mixture of HF molecules and their dissociated ions in solution.
Understanding dissociation is important because it affects properties such as pH and electrical conductivity. In the case of HF, the presence of hydrogen ions contributes to its acidic nature, while the fluoride ions can interact with other elements or compounds, affecting solubility and reactivity.

Balancing Equations

Balancing chemical equations is a fundamental skill in chemistry. It ensures that the law of conservation of mass is followed. According to this law, matter cannot be created or destroyed in a chemical reaction, so the number of atoms for each element must be the same on both sides of the equation.
In the given equation \(\text{HF(aq)} \rightleftharpoons \text{H}^{+}(\text{aq}) + \text{F}^{-}(\text{aq})\) for HF dissociation, we see that it is already balanced. The equation shows one molecule of HF breaking apart into one hydrogen ion and one fluoride ion.
Key steps in balancing generally include:

• Identifying the total number of atoms of each element on both the reactant and product sides.
• Adjusting coefficients to ensure that each element has the same number of atoms on each side. Coefficients are the numbers placed in front of compounds that adjust how many molecules or formula units are involved.
• Checking the balance of charge, particularly in reactions involving ions, to ensure that the total charge is conserved.

Mastering balancing is essential for solving more complex equations and understanding reaction dynamics.