To determine which substance is a bad conductor of electricity, we need to consider the electrical conductivity of each option:
- Diamond: Diamond is a crystal form of carbon where each carbon atom is bonded to four other carbon atoms in a rigid tetrahedral structure. This structure lacks free electrons, making diamond a poor conductor of electricity.
- Gold: Gold is a metal with high electrical conductivity due to the presence of free-moving electrons, making it an excellent conductor of electricity.
- Silver: Silver is one of the best conductors of electricity. It has a high number of free electrons, allowing electricity to pass through it very efficiently.
- Graphite: Graphite is another form of carbon but has a layered structure where each carbon atom is bonded to three others, creating a 'sheet' with delocalized electrons that can move freely. This mobility of electrons makes graphite a good conductor of electricity.
Therefore, Diamond is the substance that is a bad conductor of electricity.