Many Residential Microwave Ovens Operate at 900 Watts

Many residential microwave ovens operate at 900 watts. How long will it take a 900 watt microwave oven to raise the temperature of 1 cup of water at 23°C to steam at 105°C? The specific heat capacity of water is 4.184 J·K^-1·g^-1 and the specific heat capacity of steam is 4.215 J·K^-1·g^-1. The density of water can be assumed to be 1.00 g·ml^-1. For water, DH_vap=40.66 kJ·mol^-1. 1 cup=0.2366, 1 W=1 J·s^-1

A) 11.4 min
B) 38 seconds
C) 9.9 min
D) 1.5 min
E) None of the above