Hydroxide

Hydroxide refers to the negatively charged polyatomic ion containing oxygen and hydrogen atoms. It's often found in compounds called hydroxides, which can be alkaline or basic in nature and are essential in various chemical reactions and industrial processes. Hydroxide symbol is OH⁻. Let’s explore more about it.

1.0Hydroxide Formula

Hydroxide formula is OH- , Which includes a diatomic anion comprising oxygen and hydrogen, forming a covalent bond and carrying a negative charge. It functions as a nucleophile, ligand, catalyst, and base.

Metals, such as aluminum, magnesium, or sodium, often form hydroxides as positively charged compounds. Inorganic hydroxides like calcium hydroxide and sodium hydroxide are critical industrial alkalis.

Hydroxide

Hydroxide ions bound to electropositive elements can release hydrogen cations (H+), transforming the compound into an acid. While substances with "hydroxide" in their names often contain hydroxyl groups, they're typically covalent compounds, not ionic hydroxides.

2.0Chemical Properties of Hydroxide

  • Basic Nature: Hydroxide ions ( OH- ) are strong bases, known for their ability to accept protons (H+) and react with acids.
  • Reactivity: They exhibit nucleophilic behavior, attacking electrophilic sites in chemical reactions.
  • Ionization: Hydroxides dissociate in water, releasing hydroxide ions, which contributes to their alkaline properties.
  • Formation: Hydroxide ions can form covalent bonds with other elements or molecules, creating compounds like metal hydroxides (e.g., sodium hydroxide, calcium hydroxide).

3.0Hydroxide Ion Formation

The hydroxide ion ( OH-) forms when an oxygen atom shares a covalent bond with a hydrogen atom. In this covalent bond, the hydrogen atom donates its electron to the oxygen atom. As a result, the oxygen atom gains an additional electron, leading to an excess negative charge, while the hydrogen atom becomes positively charged.

This bond formation results in a negatively charged hydroxide ion, denoted as OH-. The negative charge comes from the extra electron gained by the oxygen atom. The hydroxide ion exists primarily in aqueous solutions, where it is highly reactive and plays a crucial role in determining the basicity of the solution.

4.0Inorganic Hydroxides

Inorganic hydroxides are chemical compounds composed of hydroxide ions (OH- ) combined with metal ions. Examples:

Inorganic Hydroxides

  • Sodium Hydroxide (NaOH): Commonly known as caustic soda, used in soap making, chemical manufacturing, and as a cleaning agent.
  • Potassium Hydroxide (KOH): Known as caustic potash, used in the production of soaps, detergents, and as an electrolyte.
  • Calcium Hydroxide (Ca(OH)₂): Also called slaked lime, used in agriculture, construction, and as a pH regulator in water treatment.
  • Magnesium Hydroxide (Mg(OH)₂): Known for its use as an antacid to neutralize excess stomach acid and as a laxative.
  • Barium Hydroxide (Ba(OH)₂): Primarily utilized in laboratories for analytical purposes and in organic synthesis.
  • Lithium Hydroxide (LiOH): Used in air purification systems aboard spacecraft and submarines to remove carbon dioxide from the air.
  • Strontium Hydroxide (Sr(OH)₂): Applied in the production of strontium chromate pigments and other strontium compounds used in fireworks and flares.
  • Aluminum Hydroxide (Al(OH)₃): Found in antacids and used as a gelatinous precipitate in water treatment for its ability to remove impurities.
  • Cesium Hydroxide (CsOH): Often utilized in organic synthesis and as a strong base in some chemical reactions.

Reactivity: Inorganic hydroxides exhibit high reactivity due to the hydroxide ions' ability to readily donate OH- ions, leading to basic properties and reactions with acids.

5.0Applications of Hydroxide

  • Industrial Uses: Sodium hydroxide (lye) and potassium hydroxide are vital in manufacturing industries like soap, paper, and textiles.
  • Chemical Processes: They play a role in various chemical reactions, particularly in neutralization reactions with acids to form salts and water.
  • Water Treatment: Metal hydroxides help in water purification by precipitating impurities.
  • Catalysis: Hydroxide ions act as catalysts in various reactions, like in the hydrolysis of esters or other organic compounds.
  • Medicinal: Some antacids use metal hydroxides to neutralize stomach acid.

Frequently Asked Questions

The definition of hydroxide involves a negatively charged ion formed when an oxygen atom is bonded to a hydrogen atom. It carries a single negative charge and exhibits basic properties.Hydroxide chemical formula is OH⁻.

No, not all hydroxides are soluble in water. While some, like sodium hydroxide and potassium hydroxide, are highly soluble, others like calcium hydroxide are sparingly soluble.

Some hydroxides, especially in concentrated or solid form, can be corrosive and harmful to skin and tissues due to their strong alkaline nature.

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