The compound barium sulfide, BaS is soluble in water. Write the net ionic equation for the dissociation reaction that occurs when solid barium sulfide dissolves in water:
Use the pull-down boxes to specify states such as (aq) or (s).
The correct answer and explanation is :
Net Ionic Equation for the Dissociation of BaS in Water
When barium sulfide (BaS) dissolves in water, it dissociates completely into its ions:
[
\text{BaS (s)} \rightarrow \text{Ba}^{2+} \text{(aq)} + \text{S}^{2-} \text{(aq)}
]
Explanation (300 Words)
Barium sulfide (BaS) is an ionic compound consisting of Ba²⁺ (barium ion) and S²⁻ (sulfide ion). In solid form, these ions are held together by strong ionic bonds in a crystal lattice. However, when BaS is added to water, the polar water molecules surround the individual ions and overcome these ionic bonds, leading to dissociation.
This dissociation is a physical process where the solid BaS separates into free ions in solution. Since BaS is highly soluble in water, it dissolves completely, meaning that every formula unit of BaS separates into one Ba²⁺ ion and one S²⁻ ion.
To write the net ionic equation, we follow these steps:
- Identify the reactant: BaS is a solid (( s )) and does not ionize until it dissolves.
- Identify the products: The dissociation produces Ba²⁺ (aq) and S²⁻ (aq).
- Exclude spectator ions: Since there are no additional substances reacting or precipitating, the equation remains simple.
Thus, the net ionic equation is:
[
\text{BaS (s)} \rightarrow \text{Ba}^{2+} \text{(aq)} + \text{S}^{2-} \text{(aq)}
]
Key Points
- Solubility: BaS is soluble, so it fully dissociates.
- Complete Dissociation: The compound separates into Ba²⁺ and S²⁻ ions.
- Physical Process: No chemical reaction occurs; it’s just breaking ionic bonds.
This equation accurately represents the dissolution of barium sulfide in water.