A kettle containing 3.00 liters of water at a temperature of 18°C is placed on an electric stove and begins to boil in three minutes.

(a) Write an energy balance on the water and determine an expression for dT/dt, neglecting evaporation of water before the boiling point is reached, and provide an initial condition. Sketch a plot of T versus t from t = 0 to t = 4 minutes.

(b) Calculate the average rate (W) at which heat is being added to the water. Then calculate the rate (g/s) at which water vaporizes once boiling begins.

(c) The rate of heat output from the stove element differs significantly from the heating rate calculated in Part (b). In which direction, and why?