Question

Determine the energy needed to change a
.80kg block of ice at -13deg C into steam at 101deg C

Answer 1

  Heat required to raise the temperature of ice from -13 °C to 0 °C Use the formula

0.80 kg = 800 g

q1 = mcΔT = 800*2.09*( 0--13) = 21736 J

Heat required to convert 0 °C ice to 0 °C water

q2 = m·ΔH_f = 800*334 =267200 J

Heat required to raise the temperature of 0 °C water to 100 °C water

q3=mcΔT =800*4.18*(100-0) =334400 J

Heat required to convert 100 °C water to 100 °C steam

q4 =q = m·ΔH_v = 800*2257 = 1805600 J

Heat required to convert 100 °C steam to 101 °C steam

q5=mcΔT =800*2.09*(101-100) =1672 J

tottal heat Q =q1+q2+q4+q5 = 2430608 J = 2430.61 kJ answer