One disadvantage of making tools and weapons from copper is that the metal is very malleable, which means that copper tools and weapons are easily bent and damaged. We can explain the malleability of Cu(and other metals) in terms of the diffuse metallic bonds between its atoms (Section 11.3). A solid piece of copper has their cubic closest-packed (ccp) structure (Section 11.1) and their cubic closest-packed (ccp) structure (Section 11.3). A solid piece of copper has an enormous number of layers of tightly packed, two-dimensional planes of copper atoms that are only weakly bonded to each of their nearest neighbors. This arrangement gives the atoms in one plane the ability, under stress, to slip past atoms stop slipping, many have different atoms as nearest neighbors but the overall crystal structure is still cubic closest-packed. The ease with which copper atoms slip past each other made it easy for prehistoric metalworkers to hammer copper metal into spear points and shields, but it also meant that those objects could easily be damaged in the heat of battle.
Substitutional Alloys
About 5500 years ago, people living around the Aegean Sea discovered that mixing molten tin and copper together produced bronze, a new material that was much stronger than either tin or copper alone. Its discovery ushered in the Bronze Age. Bronze is an alloy, a metallic material made when a host metal is blended with one or more other elements, which may or may not be metals, changing the properties of the host metal. Alloys can be a homogeneous alloy, a solid solution (homogeneous mixture) in which the atoms of the added element(s) (in this caetin) are randomly but uniformly distributed among the atoms of the host (copper, for example). Some alloys are heterogeneous alloys because a sample has small "islands" within the larger matrix where different metals are in contact. Still others are intermetalli compounds because they have a reproducible stoichiometry and constant composition.
One disadvantage of making tools and weapons from copper is that the metal is very malleable, which means that copper tools and weapons are easily bent and damaged. We can explain the malleability of Cu(and other metals) in terms of the diffuse metallic bonds between its atoms (Section 11.3). A solid piece of copper has their cubic closest-packed (ccp) structure (Section 11.1) and their cubic closest-packed (ccp) structure (Section 11.3). A solid piece of copper has an enormous number of layers of tightly packed, two-dimensional planes of copper atoms that are only weakly bonded to each of their nearest neighbors. This arrangement gives the atoms in one plane the ability, under stress, to slip past atoms stop slipping, many have different atoms as nearest neighbors but the overall crystal structure is still cubic closest-packed. The ease with which copper atoms slip past each other made it easy for prehistoric metalworkers to hammer copper metal into spear points and shields, but it also meant that those objects could easily be damaged in the heat of battle.
Substitutional Alloys
About 5500 years ago, people living around the Aegean Sea discovered that mixing molten tin and copper together produced bronze, a new material that was much stronger than either tin or copper alone. Its discovery ushered in the Bronze Age. Bronze is an alloy, a metallic material made when a host metal is blended with one or more other elements, which may or may not be metals, changing the properties of the host metal. Alloys can be a homogeneous alloy, a solid solution (homogeneous mixture) in which the atoms of the added element(s) (in this caetin) are randomly but uniformly distributed among the atoms of the host (copper, for example). Some alloys are heterogeneous alloys because a sample has small "islands" within the larger matrix where different metals are in contact. Still others are intermetalli compounds because they have a reproducible stoichiometry and constant composition.
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