Answer:
Explanation:
A. conducts electricity in both solid and liquid state.
Metal
B. conducts electricity in solid state but its electrical conductivity in liquid state is unknown. Also it burns at a vey high temperature to give off carbon dioxide gas.
Graphite
C. conducts electricity in liquid state but not in solid state
Ionic compound
D. does not conduct electricity in any state
Covalent compound
A metal is a substance that conducts both heat and electricity in solid and liquid state. They do this by the presence of free mobile electrons within their atomic space.
Graphite is a non - metal but it has free mobile electrons within its carbon frame work that allows of electrical conduction.
Ionic compounds are conductors only in molten state. In solid state, they do not conduct electricity and are called electrolytes in their liquid or molten form.
Covalent compounds do not ionize in solution and will not have ions which can conduct electric current.
