Yes, metals will conduct electricity in liquid form because of the free electrons.
By definition, a solid metal, including liquid mercury, in its elemental form should conduct electricity. Under what condition a metal cannot conduct electricity? Normally when a metal is oxidized, the result is highly resistive, but then the oxide film (such as rust) is no longer considered metallic. Some metals, such as sodium, don't normally exist in its elemental form in nature. If these metals are somehow kept out of trouble (air), they too should conduct electricity. ==================================
Copper sulphate can conduct electricity. However, this will only happen when it is in liquid or gaseous state but not in solid form.
Potassium bromide can only conduct electricity when it is in liquid form.
Metals conduct electricity as a result of the way they bond to form alloys. Their configuration is like positive ions in an "electron sea", which means that the electricity can travel easily through the electrons.
Iodine is covalent so it does not conduct electricity in a solid, however it will conduct in a liquid or molten state. The reason why it cannot conduct in a solid is that electrons cannot move freely through it.
Ionic bonds are generally solids, with high melting and boiling points. They form crystals, are soluble in water, and only conduct electricity in liquid state. They donate/receive electrons to form bonds.
Naphthalene is a Ionic Substance. Hence, Ionic substance do not conduct when solid. But they do conduct when melted or dissolved in water - and they decompose at the same time. Therefor molten Naphthalene conduts electricity as the ions become free to move when dissolved in water.
Metals conduct electricity. Metals ionise [lose one or more electrons] to form positively charged ions - cations.
Any solid metal plus liquid mercury in their elemental form.
Potassium is a metal. Like other metals, potassium will conduct electricity in both the solid and liquid (or molten) forms. But because potassium is so very reactive, you will never find it in metallic form on earth, unless it is specially prepared and stored, usually in a sealed container submerged in an inert liquid. Potassium is found in nature as ionic salts. Ionic salts conduct electricity in a molten state, but not a solid state.
Metals lose electrons to form cations. These ions help in conducting electricity.
As aluminium oxide is an ionic compound, it conducts electricity in molten state.