| any of the group of univalent metals including potassium, sodium, lithium, rubidium, cesium, and francium, whose hydroxides are alkalis. |
| alkali metal n. Any of a group of soft, white, low-density, low-melting, highly reactive metallic elements, including lithium, sodium, potassium, rubidium, cesium, and francium. |
alkali metal n.
Any of a group of soft, white, low-density, low-melting, highly reactive metallic elements, including lithium, sodium, potassium, rubidium, cesium, and francium.
| alkali metal
Any of a group of soft metallic elements that form alkali solutions when they combine with water. They include lithium, sodium, potassium, rubidium, cesium, and francium. Except for cesium, which has a gold sheen, alkali metals are white. The alkali metals have one electron in their outer shell, and therefore react easily with other elements and are found in nature only in compounds. See Periodic Table. |