Thallium (Tl)

Element number 81, from the other metals family.

Thallium facts

Symbol
Tl
Atomic number
81
Atomic mass
204.38
Family
Other metals
Period
6
Group
13

What does thallium react with?

Thallium makes a new substance with 7 other elements and chemicals in our lab:

  • Thallium + OxygenThallium(I) oxide 4Tl + O₂ → 2Tl₂O · When heated · Try it
  • Thallium + FluorineThallium(I) fluoride 2Tl + F₂ → 2TlF · At room temperature · Try it
  • Thallium + SulfurThallium(I) sulfide 2Tl + S → Tl₂S · When heated · Try it
  • Thallium + ChlorineThallium(I) chloride 2Tl + Cl₂ → 2TlCl · When heated · Try it
  • Thallium + BromineThallium(I) bromide 2Tl + Br₂ → 2TlBr · When heated · Try it
  • Thallium + IodineThallium(I) iodide 2Tl + I₂ → 2TlI · When heated · Try it
  • Thallium + Hydrochloric AcidThallium(I) chloride + hydrogen gas 2Tl + 2HCl → 2TlCl + H₂ · At room temperature · Try it

It also blends into a mixture, like an alloy, with 74 other metals when melted together.

Nothing happens when it's simply mixed with 17 of the others. 21 pairings have never been tried, because not enough atoms have ever existed.