Mercury is the metal that is found in a liquid state at room temperature, while sodium is a solid metal. Mercury has a low melting point of -38.83 degrees Celsius (-37.89 degrees Fahrenheit), which allows it to exist as a liquid under normal conditions. Sodium, on the other hand, has a melting point of 97.72 degrees Celsius (207.9 degrees Fahrenheit) and is typically found in a solid state.