| thallium. |
| (in Turkey) lira; liras. |
| time loan. |
| 1. | Also, t.l. trade last. |
| 2. | trade list. |
thal·li·um  (thāl'ē-əm)  n. Symbol Tl A soft, malleable, highly toxic metallic element, used in photocells, infrared detectors, low-melting glass, and formerly in rodent and ant poisons. Atomic number 81; atomic weight 204.38; melting point 303.5°C; boiling point 1,457°C; specific gravity 11.85; valence 1, 3. See Table at element. [thall(o)- (from its green spectral line) + -ium.] |
| Tl The symbol for the element thallium. |
| TL or t/l abbr. total loss |
Tl
The symbol for the element thallium.
| tl Tagalog |
| Tl thallium |
TL
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Tl
(Tl), chemical element, metal of main Group IIIa, or boron group, of the periodic table, poisonous and of limited commercial value. Like lead, thallium is a soft, low-melting element of low tensile strength. Freshly cut thallium has a metallic lustre that dulls to bluish gray upon exposure to air. The metal continues to oxidize upon prolonged contact with air, generating a heavy nonprotective oxide crust. Thallium dissolves slowly in hydrochloric acid and dilute sulfuric acid and rapidly in nitric acid.
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