When elementary chromium is put in water at room temperature, it does not react. This stable behavior is primarily due to chromium's inherent inertness.
Behavior of Elementary Chromium
Elementary chromium (Cr), the pure metallic form, exhibits a high degree of stability when exposed to water at typical room temperatures. Unlike more reactive metals, it does not corrode, rust, or dissolve. This resistance makes chromium an incredibly valuable material, particularly for applications requiring corrosion protection, such as in chrome plating. Its unreactive nature in water is a key characteristic, contributing to its widespread use in various industries.
Reactions of Chromium Compounds in Water
While elemental chromium is largely unreactive, the behavior of various chromium compounds in water can differ significantly. Many compounds of chromium are generally considered to be relatively water-insoluble.
Specific Solubility of Chromium (III) Compounds
The solubility of chromium compounds largely depends on their specific chemical form and oxidation state. For instance, many chromium (III) compounds exhibit insolubility in water. This is often attributed to their tendency to bind with floating particles present in water, which prevents them from fully dissolving.
However, there are notable exceptions within the chromium (III) category that are water-soluble:
- Chromium (III) oxide (Cr₂O₃): This compound is an exception and can dissolve in water.
- Chromium (III) hydroxide (Cr(OH)₃): Similar to the oxide, chromium (III) hydroxide also demonstrates solubility in water.
To summarize the interactions of chromium and its forms with water:
| Type of Chromium | Reaction/Solubility in Water (at room temperature) | Notes |
|---|---|---|
| Elementary Chromium | No reaction | Highly inert; used for corrosion resistance |
| Many Chromium Compounds | Relatively insoluble | General behavior of various chromium compounds |
| Chromium (III) Compounds | Generally insoluble | Often binds to floating particles in water |
| Chromium (III) Oxide (Cr₂O₃) | Soluble | One of the specific water-soluble exceptions |
| Chromium (III) Hydroxide (Cr(OH)₃) | Soluble | Another specific water-soluble exception |
For more general information on the properties of chromium, you can refer to resources like the Royal Society of Chemistry.
