why deos magnesium show hcp but not copper
Asked by banga71
| 14th Apr, 2017,
10:52: AM
Expert Answer:
- The crystal structure adopted by a particular metal at a given temperature and pressure will be the structure which provides for the minimisation of free energy.
- The atoms of the metal will form arrangements which ensure that the electron orbitals that bond them have the repulsion/attraction due to bond length all contribute to the lowest energy state.
- Each metal has a slightly different metallic radius, which is defined as half of the distance between the two adjacent metal ions in the metallic lattice.
- Depending on the metallic radius, the lowest energy state would be achieved by different atomic arrangements.
- For the alkaline earth metals with the smaller metallic radii (beryllium and magnesium), the lowest energy state is the HCP structure.
- To achive lowest energy level, copper forms FCC.
- The crystal structure adopted by a particular metal at a given temperature and pressure will be the structure which provides for the minimisation of free energy.
- The atoms of the metal will form arrangements which ensure that the electron orbitals that bond them have the repulsion/attraction due to bond length all contribute to the lowest energy state.
- Each metal has a slightly different metallic radius, which is defined as half of the distance between the two adjacent metal ions in the metallic lattice.
- Depending on the metallic radius, the lowest energy state would be achieved by different atomic arrangements.
- For the alkaline earth metals with the smaller metallic radii (beryllium and magnesium), the lowest energy state is the HCP structure.
- To achive lowest energy level, copper forms FCC.
Answered by Prachi Sawant
| 15th Apr, 2017,
09:23: PM
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