Every metal conducts electricity. This is due to the metallic bonding found within metal elements. In metallic bonding, the outer electrons are delocalised (free to move). This produces an electrostatic force of attraction between the positively charged metal ions, and the negatively charged delocalised electrons.
The ability of metals to conduct electricity stems from their delocalised electrons. As these are free to move, an electrical current can flow through metallic materials.
When metals form ions, they give away one or more of their outer electrons. Some metals, such as lithium or sodium, lose their electrons very easily. Other metals for example silver or gold do not give away electrons easily. The electrochemical series is a list of metals arranged in rank order of how easily the metal atoms lose electrons.
This can be found in the SQA Data Booklet.