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ALEVEL CHEM giant covalent structure

In group 3 Why does the giant covalent structure have the highest melting point over metallic solids, molecular solids and atomic solid?
Also, does this happen with other groups too?
Original post by lane_in_pain
In group 3 Why does the giant covalent structure have the highest melting point over metallic solids, molecular solids and atomic solid?
Also, does this happen with other groups too?


Well atomic solids only have weak London forces between molecules that require very little energy to break giving them melting points.

For metallic and giant covalent structures, it varies between structure and metal, e.g metals with greater charge densities have the highest melting points like Al3+ like group 3 metals in the upper periods of the table, e.g Aluminium. Whereas those like Caesium with small charge densities have relatively low melting points.
Original post by seals2001
Well atomic solids only have weak London forces between molecules that require very little energy to break giving them melting points.

For metallic and giant covalent structures, it varies between structure and metal, e.g metals with greater charge densities have the highest melting points like Al3+ like group 3 metals in the upper periods of the table, e.g Aluminium. Whereas those like Caesium with small charge densities have relatively low melting points.

Thanks for your response- its very helpful. can I ask you why I am incorrect in this statement?:
More valence electrons make electrostatic attractions increase, as they are attracted to the + nucleus. This means the melting point is higher as the electrons are attracted to the + nucleus of the atom next to it. // I would love to know what does makes electrostatic attractions increase, if it isn’t this.
Original post by lane_in_pain
Thanks for your response- its very helpful. can I ask you why I am incorrect in this statement?:
More valence electrons make electrostatic attractions increase, as they are attracted to the + nucleus. This means the melting point is higher as the electrons are attracted to the + nucleus of the atom next to it. // I would love to know what does makes electrostatic attractions increase, if it isn’t this.

Its not just valence electrons, its the number of electrons in the WHOLE molecule.
Original post by seals2001
Its not just valence electrons, its the number of electrons in the WHOLE molecule.

thank u

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