Metals can be bent and shaped because the layers of atoms in a giant metallic structure can slide over each other
An alloy is a mixture of two or more elements, at least one of which is a metal
Alloys are harder than pure metals because the regular layers in a pure metal are distorted by atoms of different sizes in an alloy
The atoms in pure iron are arranged in layers, which can easily slide over each other. In alloys, the layers cannot slide so easily, because atoms of other elements distort the layers
Alloys are better metals because they distort the lattice structure:
layers are unable to slide that easily
stronger
Delocalised electrons in metals enable electricity and thermal energy to be transferred through a metal easily
Pure iron would not be suitable for a hip replacement because pure iron is soft