Alkaline metals belong to Group 1 of the periodic table and include the elements lithium, sodium, potassium, rubidium, cesium and francium.
Properties of alkali metals
Alkaline metals are a group of chemical elements that are in the first main group of the periodic table of elements. They are known for their high reactivity, especially with water.
- These metals are particularly reactive with water, producing particularly strong heat. Their low ionization energy allows them to donate electrons easily, which explains their high reactivity.
- They have a relatively low density and are so soft that they can be easily cut with a knife. Lithium, the lightest metal, is even less dense than water.
- Compared to other metals, alkali metals have low melting and boiling points, which continue to decrease as the atomic number increases. This makes them particularly sensitive to heat.
- Alkaline metals are relatively good electrical conductors, which makes them important components in batteries, for example. However, their conductivity decreases as the atomic number increases. Within the group of metals, they are actually the weakest conductors.
- Alkaline metals actually have a characteristic silvery shine, but this is quickly lost in air due to oxidation. Therefore, they often need to be stored in oils such as petroleum or paraffin to protect them from reaction with air and moisture.
Alkaline metals in industry
Due to their special properties, alkali metals play an important role in industry – in very different areas.
- Lithium is a main component of rechargeable batteries, particularly lithium-ion batteries. These batteries are characterized by high energy density and are used in smartphones, laptops and electric vehicles.
- Sodium is used in the form of sodium carbonate (soda) in large quantities to make glass and as a raw material in the chemical industry. It also plays an important role in the production of caustic soda and other chemical compounds.
- Potassium compounds, especially potassium chloride, are often used as fertilizers in agriculture. They are important for healthy plant growth and improve soil fertility.
- Rubidium is used to make atomic clocks. A rubidium atomic clock uses a special property of the rubidium atom to measure time very precisely. While these clocks are not as accurate as the best atomic clocks that use cesium, they are smaller, cheaper, and still very accurate.
- Cesium has a wide range of applications. It is used, among other things, in the production of photomultipliers and photocells, and is of particular importance for infrared radiation. The chemical element is also used in infrared light sets for night vision devices. In addition, cesium plays a role in the production of stealth smoke munitions as well as infrared-transmissive windows, lenses and prisms.