108Hs

Hassium

Transition metalunknownblock d

The heaviest element whose chemistry has actually been measured, forming a volatile tetroxide exactly as osmium directly above it does.

Atomic number	108
Mass number (longest-lived isotope)	269 g/mol
This element has no stable isotope, so it has no standard atomic weight. The figure above is the mass number of its longest-lived isotope — a convention, not a measurement of a natural mixture.
Group · period	8 · 7
Electron configuration	[Rn] 5f¹⁴ 6d⁶ 7s²

About Hassium

In 2002 a team at GSI made a handful of hassium atoms, let them react with oxygen, and watched hassium tetroxide condense on a cooled detector surface at almost the same temperature as osmium tetroxide — a five-atom experiment that placed element 108 squarely in group 8. That remains among the highest atomic numbers for which real chemical behaviour, rather than prediction, is known. Hassium is named after Hesse, the German state containing Darmstadt, where GSI made elements 107 through 112. Theory expects hassium-borne isotopes near neutron number 184 to sit on the predicted island of stability, and hassium-277m's eleven-second half-life is one of the hints that the island is really there.

Use 269 g/mol in these solvers

Moles from Mass (n = m/M)

n = \frac{m}{M}

Opens with M = 269 g/mol already filled in

Gas Density from Molar Mass

\rho = \frac{PM}{RT}

Opens with M = 269 g/mol already filled in

Faraday's Law of Electrolysis (m = QM/nF)

m = \frac{Q M}{n F}

Opens with M = 269 g/mol already filled in

Ion Concentration as CaCO₃ Equivalent

C_{\mathrm{CaCO_3}} = C_{\mathrm{ion}} \times \frac{50.04}{\mathrm{EW}}

Opens with EW = 269 g/mol already filled in

Acid Feed to Reduce Alkalinity

\dot m = \frac{\Delta \mathrm{Alk} \, Q \times \frac{\mathrm{EW}}{50.04}}{p/100\%}

Opens with EW = 269 g/mol already filled in

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