Write equations to show how the substances listed in Problem 3.75 give ions when dissolved in water.
a. H₂CO₃
b. HCN
c. Mg(OH)₂
d. KOH

Verified step by step guidance

1. Identify the substances listed in Problem 3.75. These are likely ionic compounds or acids that dissociate into ions when dissolved in water. For example, common substances might include NaCl, HCl, or Ca(OH)₂.
2. For each substance, determine whether it is an ionic compound, a strong acid, or a strong base. Ionic compounds dissociate into their respective cations and anions, while strong acids and bases ionize completely in water.
3. Write the dissociation equation for each substance. For example, for NaCl, the equation would be: $\mathrm{NaCl}\left(\mathrm{aq}\right)\to \mathrm{Na}^+\left(\mathrm{aq}\right)+\mathrm{Cl}^-\left(\mathrm{aq}\right)$.
4. For polyatomic ions or acids, ensure you correctly represent the dissociation. For example, for H₂SO₄, the first dissociation step is: $H_2\mathrm{SO}{4}_2\left(\mathrm{aq}\right)\to H^+\left(\mathrm{aq}\right)+\mathrm{HSO}{4}_1^-\left(\mathrm{aq}\right)$.
5. Repeat this process for all substances listed in Problem 3.75, ensuring that the charges on the ions are balanced and the states of matter (e.g., (aq) for aqueous) are included in the equations.

Key Concepts

Dissociation of Ionic Compounds

Dissociation refers to the process by which ionic compounds separate into their constituent ions when dissolved in water. For example, sodium chloride (NaCl) dissociates into Na⁺ and Cl⁻ ions. This process is crucial for understanding how substances behave in aqueous solutions and is fundamental in predicting the resulting ions from various compounds.

Solubility Rules

Solubility rules are guidelines that help predict whether a given ionic compound will dissolve in water. These rules indicate which ions are generally soluble or insoluble in water, aiding in the identification of the ions produced when a substance dissolves. Understanding these rules is essential for determining the behavior of different compounds in aqueous solutions.

Chemical Equations

Chemical equations represent the transformation of reactants into products, illustrating the dissociation of compounds in water. They provide a concise way to show the ions formed during dissolution, such as writing NaCl(s) → Na⁺(aq) + Cl⁻(aq). Mastery of writing and balancing these equations is vital for accurately conveying chemical reactions and understanding the resulting ionic species.