12Mg

Magnesium

Alkaline earth metalsolidblock s

The lightest structural metal and the atom at the centre of chlorophyll, so it sits behind every green leaf on the planet.

Atomic number	12
Standard atomic weight	24.305 g/mol
Group · period	2 · 3
Electron configuration	[Ne] 3s²

About Magnesium

Every chlorophyll molecule is a porphyrin ring wrapped around a single magnesium ion, which means magnesium mediates essentially all photosynthesis and, indirectly, the food supply. In the metals world it is the lightest structural option at 1.74 g/cm³, about two-thirds the density of aluminium, and it goes into gearbox housings, laptop shells and cast wheels. Its notoriety comes from how it burns: magnesium ignites around 650 °C and burns at over 3000 °C with a brilliant white light that made it the flash powder of Victorian photography and the incendiary filler of the RAF's 4 lb bombs. Water does not put it out — it strips the oxygen out of steam and liberates hydrogen — which is why a magnesium fire is fought with dry powder and never a hose. It is the eighth most abundant element in the crust.

Use 24.305 g/mol in these solvers

Moles from Mass (n = m/M)

n = \frac{m}{M}

Opens with M = 24.305 g/mol already filled in

Gas Density from Molar Mass

\rho = \frac{PM}{RT}

Opens with M = 24.305 g/mol already filled in

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

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

Opens with M = 24.305 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 = 24.305 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 = 24.305 g/mol already filled in

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