Water is boiled in a pan on a stove at sea level. During 15 min of boiling, it is observed that 150 g of water has evaporated. Then the rate of heat transfer to the water is
A)26.8 kJ/min
B)22.6 kJ/min
C)0.45 kJ/min
D)4.2 kJ/min
E)16.9 kJ/min

Question

Quizplus · Accepted Answer

Solved by EES Software. Solutions can be verified by copying-and-pasting the following lines on a blank EES screen. 
m_evap=0.15 "kg"
P=101.325 "kPa"
time=15 "min"
Q*time=m_evap*h_fg "kJ"
h_f=ENTHALPY(Steam_ IAPWS, x=0,P=P)
h_g=ENTHALPY(Steam_ IAPWS, x=1,P=P)
h_fg=h_g-h_f
"Some Wrong Solutions with Common Mistakes:"
W1_Q*time=m_evap*h_g "Using h_g" 
W2_Q*time*60=m_evap*h_g "Using s instead of min for time"
W3_Q*time=m_evap*h_f "Using h_f"

Water Is Boiled in a Pan on a Stove at Sea