Write the ions present in solution of K2CO3. Express your answers as chemical formulas separated by a comma. Identify all of the phases in your answers.
The Correct Answer and Explanation is :
When potassium carbonate (K₂CO₃) dissolves in water, it dissociates into its constituent ions:
K₂CO₃ (s) → 2 K⁺ (aq) + CO₃²⁻ (aq)
This means that for every formula unit of K₂CO₃ that dissolves, two potassium ions (K⁺) and one carbonate ion (CO₃²⁻) are produced in the aqueous phase.
Explanation:
- Dissociation of Ionic Compounds:
- Ionic compounds like K₂CO₃ consist of positively charged cations and negatively charged anions held together by electrostatic forces.
- When such compounds dissolve in water, the polar water molecules surround and separate these ions, allowing them to move freely in solution.
- Stoichiometry of K₂CO₃:
- The chemical formula K₂CO₃ indicates that each formula unit contains two potassium ions (K⁺) and one carbonate ion (CO₃²⁻).
- Phases of Ions:
- In the dissociation equation, “(s)” denotes a solid, indicating that K₂CO₃ is in solid form before dissolution.
- “(aq)” denotes an aqueous solution, indicating that the ions are dissolved in water.
- Electrical Conductivity:
- The presence of free-moving ions in the aqueous solution allows it to conduct electricity, a property characteristic of electrolytes.
- Reversibility:
- The dissociation of K₂CO₃ in water is a reversible process. Under certain conditions, such as evaporation of water, the ions can recombine to form solid K₂CO₃ again.
Understanding the dissociation of K₂CO₃ is fundamental in various chemical processes, including acid-base reactions, precipitation reactions, and in the study of colligative properties of solutions.
For a visual explanation, you might find the following video helpful: