In hydroxides, a covalent bond links a hydrogen atom with an oxygen atom. The negative-charged hydroxide ion serves as a catalyst, nucleophile, ligand, base, etc. Hydroxide is also known as the hydroxyl radical, hydroxide ion, or hydroxyl ion.
An oxide is a chemical molecule that contains one or more oxygen atoms and another element. Most stable oxides, such as alumina (aluminium oxide), calcium oxide, and others, have oxygen in the -2 oxidation state.
Classification of oxides
Oxides are classified as basic, acidic, amphoteric or neutral, depending on their acid-base properties.
- A basic oxide is an oxide that produces a base in water [alkaline and alkali metal oxides].
- Acidic oxide is an oxide that forms an acid when it reacts with water [SO3, CO2, etc.].
- An amphoteric substance can react chemically as an acid or a base [Al2O3, PbO, SnO, etc.].
- Oxide can be neither acidic nor basic [CO, NO, NO2, etc.].
Characteristics of Hydroxide
In hydroxide, two electrons share oxygen bonds with hydrogen. Hydroxide has a negative charge because an electron has been absorbed.
- Hydroxide – OH–
- Conjugate base – Oxide anion
- Conjugate acid – Water
- Monoisotopic mass – 17.003 g/mol
- Molecular Weight – 17.007 g/mol
Important Hydroxide Compounds
The chemical formula of some important hydroxide compounds, and their applications, are given here.
Lithium hydroxide (LiOH)
In a test tube, lithium reacts with water to produce lithium hydroxide (LiOH) and hydrogen gas.
|Molecular weight||23.95 g/mol|
|Melting & Boiling point||462 °C and 924°C|
Applications of LiOH
Lithium hydroxide is used in a variety of applications.
- Several lithium compounds, such as lithium chloride, lithium iodide, lithium bromide, and lithium fluoride, use lithium hydroxide (LiOH) as a starting material.
- To absorb unwanted gas, LiOH is utilised.
- The spacecraft’s scrubbers use lithium hydroxide to remove carbon dioxide from the air.
Aluminium hydroxide (Al(OH)3)
Aluminium hydroxide is a white, amorphous powder. It is soluble in alkaline and acidic solutions but not in water.
|Molecular weight||78.00 g/mol|
|Melting point||300 °C|
Uses of Al(OH)3
Aluminium hydroxide has a variety of applications.
- Aluminium hydroxide is used to treat heartburn, stomach pain, aching stomach and acid indigestion.
- It’s also used to lower phosphate levels in people who have kidney disorders.
Magnesium hydroxide (Mg(OH)2)
Magnesium hydroxide is a chemical compound with low water solubility. It’s also known as magnesium (2+) hydroxide or Milk of Magnesia.
|Molecular weight||58.3197 g/mol|
Uses of Mg(OH)2
- Magnesium hydroxide is a laxative that helps people with chronic constipation.
- Magnesium hydroxide is an antacid used to treat indigestion, heartburn, and acid reflux.
Zinc hydroxide [Zn(OH)2]
Zinc hydroxide is an inorganic chemical with the formula Zn(OH)2. Zinc hydroxide reacts with both bases and acids. When exposed to strong acid, it dissolves as an insoluble hydroxide.
|Molecular weight||99.424 g/mol|
|Melting point||125° C|
Uses of zinc hydroxide
- The zinc hydroxide is utilised as a retentive in careful dressings.
- It’s utilised in the commercial production of pigments and pesticides as an intermediate.
- The zinc component is applied to big bandages used to engross blood from wounds during medical treatments.
Sodium hydroxide (NaOH)
At room temperature, sodium hydroxide is a solid ionic chemical compound. Other names for caustic soda include Iye, soda lye, and sodium hydrate. It is produced as a byproduct of the chlorine production process. In its finest form, it is a colourless crystalline solid. Properties of sodium hydroxide are,
|Molecular weight||2.13 g/cm3|
|Melting and boiling point||318°C and 1,388°C|
Uses of NaOH
- Soaps and other detergents are made from sodium hydroxide.
- By combining chlorine with sodium hydroxide, chlorine bleach is produced.