Two factors that change the specific heat of a material are pressure and temperature. Specific heat is defined at a standard, constant pressure (usually atmospheric pressure) for materials and is generally reported at 25 °C (298.15 K). A standard temperature is used because specific heat has temperature dependence and can change at different temperature values. Specific heat is referred to as an ) As long as the temperature and pressure are at the standard referenced values and no phase change occurs, the value for the specific heat of any material remains constant regardless of the mass of the material present . 