If a solid piece of naphthalene is heated and remains at 80°c until it is completely melted, you know that 80ºc is the

The solid piece of naphthalene when heated is observed to melt after it attains the temperature of 80° C and then this 80° C is called as it melting point. After 80° C naphthalene will start to melt and get transformed into liquid state. Also if this naphthalene is allowed to cool down after 80° C it will be the freezing point of naphthalene.