Nature of science: Use theories to explain natural phenomena-the properties of metals are different from covalent and ionic substances and this is due to the formation of non-directional bonds with a "sea" of delocalized electrons. (2.2)
A metallic bond is the electrostatic attraction between a lattice of positive ions and delocalized electrons.
The strength of a metallic bond depends on the charge of the ions and the radius of the metal ion.
Alloys usually contain more than one metal and have enhanced properties.
Explanation of electrical conductivity and malleability in metals.
Explanation of trends in melting points of metals.
Explanation of the properties of alloys in terms of non-directional bonding.
Trends should be limited to s- and p-block elements.
Examples of various alloys should be covered.
The availability of metal resources, and the means to extract them, varies greatly in different countries, and is a factor in determining national wealth. As technologies develop, the demands for different metals change and careful strategies are needed to manage the supply of these finite resources
Syllabus and cross-curricular links:
Option A.6-use of metals in nanotechnology
Biology topic 2.2-water
Aim 1: Global impact of value of precious metals and their extraction processes and locations.
Aim 7: Computer simulations could be used to view examples of metallic bonding