Definition

Noun: - A radioactive element of the alkali-metal group discovered as a disintegration product of actinium: This is the scientific definition for the chemical element with 87 protons in its nucleus. It is a highly unstable, naturally occurring radioactive metal.

Usage

This term is used almost exclusively in scientific contexts, particularly in chemistry and physics, to refer to this specific element. - Francium is the element with atomic number 87. - Atomic number 87 is one of the rarest elements naturally found on Earth.

Advanced Usage

• The term is used to precisely identify the element by its fundamental property (the number of protons), which determines its position on the periodic table and its chemical identity.
• It is often used in contrast to the element's name ("francium") in educational or technical writing to emphasize its defining atomic characteristic.

Variants and Related Words

• Francium (Fr): This is the name of the element represented by atomic number 87.
• Alkali metal: The group in the periodic table to which atomic number 87 belongs.
• Radioactive element: A category describing elements like atomic number 87 that spontaneously decay.

Synonyms

• Francium
• Element 87
• Fr (its chemical symbol)

Notes

• There are no idioms or phrasal verbs associated with this specific scientific term. Its usage is strictly technical.

Noun

1. a radioactive element of the alkali-metal group discovered as a disintegration product of actinium