107Bh

Bohrium

Transition metalunknownblock d

A superheavy element whose chemistry was settled by six atoms, whose oxychloride proved it still behaves like rhenium a full row below.

Atomic number	107
Mass number (longest-lived isotope)	270 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	7 · 7
Electron configuration	[Rn] 5f¹⁴ 6d⁵ 7s²

About Bohrium

The 2000 bohrium chemistry experiment at the Paul Scherrer Institute is a landmark in how little material a measurement can need: six atoms of bohrium-267, produced one at a time over weeks, were swept into a chromatography column and their volatility as BhO₃Cl compared with the technetium and rhenium analogues. Bohrium came out less volatile than rhenium, exactly as group 7 periodicity predicts. The name honours Niels Bohr; the German team that made it in 1981 originally proposed nielsbohrium, and IUPAC shortened it, reasoning that no other element carries a first name either. Bohrium-270 has a half-life around a minute, which is long by transactinide standards.

Use 270 g/mol in these solvers

Moles from Mass (n = m/M)

n = \frac{m}{M}

Opens with M = 270 g/mol already filled in

Gas Density from Molar Mass

\rho = \frac{PM}{RT}

Opens with M = 270 g/mol already filled in

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

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

Opens with M = 270 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 = 270 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 = 270 g/mol already filled in

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