Final answer:
The value 0.81 J/g°C is the specific heat of the metal, which reflects the metal's capacity to absorb heat per gram per degree Celsius change in temperature.
Step-by-step explanation:
The specific heat of the metal, which is approximately 0.81 J/g°C, represents the heat capacity of the metal. This value indicates the amount of heat required to raise the temperature of one gram of the substance by one degree Celsius. Specific heat is an intensive property and is crucial in determining the identity of an unknown metal by comparing it to known values.