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Date: 19-1-2018
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Date: 29-11-2018
868
Date: 26-12-2018
774
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Group 3 Elemental Properties
Moreover, all dissolve readily in aqueous acid to produce hydrogen gas and a solution of the hydrated M3+(aq) ion. The chemistry of the group 3 metals is almost exclusively that of the M3+ ion; the elements are powerful reductants.
The group 3 metals react with nonmetals to form compounds that are primarily ionic in character. For example, reacting group 3 metals with the halogens produces the corresponding trihalides: MX3. The trifluorides are insoluble in water because of their high lattice energies, but the other trihalides are very soluble in water and behave like typical ionic metal halides. All group 3 elements react with air to form an oxide coating, and all burn in oxygen to form the so-called sesquioxides (M2O3), which react with H2O or CO2 to form the corresponding hydroxides or carbonates, respectively.
Element | Z | Valence Electron Configuration | Electronegativity | Metallic Radius (pm) | Melting Point (°C) | Density (g/cm3) |
---|---|---|---|---|---|---|
Sc | 21 | 4s23d1 | 1.36 | 162 | 1541 | 2.99 |
Y | 39 | 5s24d1 | 1.22 | 180 | 1522 | 4.47 |
La | 57 | 6s25d1 | 1.10 | 183 | 918 | 6.15 |
Ac | 89 | 7s26d1 | 1.10 | 188 | 1051 | 10.0 |
Scandium burns readily in oxygen to form scandium (III) oxide, Sc2O3
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