False.
Chalk is not considered soluble in water. Its main component is calcium carbonate (CaCO3).
According to the provided reference, "The solubility of calcium carbonate is extremely low in water". This means that while "an extremely minute amount of CaCO3 is able to dissolve in a normal amount of water," the vast majority remains solid. This characteristic leads to it being classified as "mostly insoluble in water."
Understanding Solubility
Solubility refers to the ability of a substance (solute) to dissolve in a solvent, typically water, to form a solution. When a substance is soluble, it breaks down and disperses evenly throughout the solvent, seemingly disappearing.
In the case of chalk:
- Solute: Chalk (primarily Calcium Carbonate, CaCO3)
- Solvent: Water (H₂O)
- Result: A suspension is formed where solid particles are dispersed but do not fully dissolve. A very tiny amount does dissolve, but it's insignificant for general classification.
Think of adding sugar to water; it dissolves completely. Adding sand to water; it settles at the bottom. Chalk behaves more like sand, classifying it as insoluble or, more precisely based on its chemical properties, having very low solubility.
Why is Chalk (Calcium Carbonate) Mostly Insoluble?
The low solubility of calcium carbonate is due to the strong ionic bonds holding the calcium (Ca²⁺) and carbonate (CO₃²⁻) ions together in its crystal structure. Water molecules, although polar, are not strong enough to effectively break these bonds and hydrate (surround) the ions to a significant extent.
Here's a simple breakdown based on the reference:
| Characteristic | Description |
|---|---|
| Main Component of Chalk | Calcium Carbonate (CaCO3) |
| Solubility of CaCO3 in Water | Extremely low |
| Amount that Dissolves | Extremely minute amount |
| Amount that Remains Solid | Most of it |
| Classification in Water | Mostly insoluble |
Therefore, based on its chemical composition and solubility properties, chalk is accurately described as mostly insoluble in water, making the statement "Is chalk soluble in water True or false?" false.
