109Mt

Meitnerium

Unknown propertiesunknownblock d

A superheavy element named for Lise Meitner, who explained nuclear fission correctly and was then passed over for the Nobel Prize entirely.

Atomic number	109
Mass number (longest-lived isotope)	278 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	9 · 7
Electron configuration	[Rn] 5f¹⁴ 6d⁷ 7s²

About Meitnerium

Lise Meitner and her nephew Otto Frisch worked out over Christmas 1938 that Otto Hahn's puzzling barium had come from a uranium nucleus splitting in two, and they named the process fission by analogy with dividing cells. Hahn took the 1944 Nobel Prize in Chemistry alone; Meitner, a refugee from Nazi Germany in Sweden, was nominated 48 times across physics and chemistry and never won. Element 109 is the correction the scientific community could still make. Nothing is known of its chemistry — three atoms were made in 1982 and no chemical experiment has ever been attempted — so its configuration here is calculated, and its category is left unknown rather than assumed to be group 9 iridium-like.

Use 278 g/mol in these solvers

Moles from Mass (n = m/M)

n = \frac{m}{M}

Opens with M = 278 g/mol already filled in

Gas Density from Molar Mass

\rho = \frac{PM}{RT}

Opens with M = 278 g/mol already filled in

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

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

Opens with M = 278 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 = 278 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 = 278 g/mol already filled in

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