A portable electric water heater transfers 255 watts of power to 5.5 L of water, where 1 W=1J/s. How much time (in minutes) will it take. … where 1 W=1J/s. How much time (in minutes) will it take for the water heater to heat the 5.5 L of water from 28 C to 42 C? (Assume that the water has a density of 1.0 g/mL.)