thallium

/'θæliəm/

Thân thiện

A scientist uses long metal tongs to hold a small, dull grey cube of thallium over a clean laboratory workbench.

Definition

1. Noun:
   • A chemical element: A soft, gray, malleable metallic element with atomic number 81 and symbol Tl. It resembles tin in appearance but tarnishes when exposed to air. It is highly toxic and is found in some minerals like zinc blende and certain iron ores.

Usage

• Primary Usage: Used to refer to the chemical element itself, often in scientific, industrial, or toxicological contexts.
  • Thallium is a heavy metal with a density similar to lead.
  • The forensic test detected traces of thallium in the sample.

Advanced Usage

• "Thallium poisoning": Refers to intoxication caused by the ingestion or exposure to thallium compounds, historically used in rodenticides and insecticides.
  • The patient's symptoms were consistent with acute thallium poisoning.

Variants and Related Words

• Thallous (adj): Relating to or containing thallium, especially in its monovalent state (Tl⁺).
  • Thallous sulfate was once a common rat poison.
• Thallic (adj): Relating to or containing thallium in its trivalent state (Tl³⁺).

Synonyms

• Element 81: Referring to its atomic number.
• Tl: Its chemical symbol.

Notes on Meaning

• The word is used almost exclusively in scientific and technical contexts (chemistry, metallurgy, toxicology, forensics). Its primary associations are with its physical/chemical properties (soft, gray, metallic, malleable), its toxicity, and its historical applications in poisons.

Học thuật

Noun

1. a soft grey malleable metallic element that resembles tin but discolors on exposure to air; it is highly toxic and is used in rodent and insect poisons; occurs in zinc blende and some iron ores

Từ đồng nghĩa

• Tl
• atomic number 81