The density of water () and specific heat of water (Cp)
The density of water changes slightly with the temperature. However, this variation has a very small effect in terms of the calculations and thus can be ignored. Thus, =8.34lb/gal (0.998kg/L). The specific heat is the amount of heat per unit mass required to raise the temperature by one degree. Cp of water is equal to 1Btu/lb °F (4.18 kJ/ (kg·°C).