Points At 1 bar, how much energy is required to heat 57.0 g of H2O(s) at-240°C t
ID: 1080964 • Letter: P
Question
Points At 1 bar, how much energy is required to heat 57.0 g of H2O(s) at-240°C to H2O(g) at 1 15.0°C? Grade STRATEGY 1. Calculate the energy needed for each temperature change or phase change individually Descrip a. the energy needed to heat 57.0 g of H20(s) from-24.0 °C to its melting point. b. the energy needed to melt 57.0 g of H2O(s) at its melting point c. the energy needed to heat 57.0 g of H2O() from the melting point to the boiling point. d. the energy needed to boil 57.0 g of H20( at its boiling point. e, the energy needed to heat 57.0 g of H2O(g) from the boiling point to 1150°C Policies You ca You ca give u You ca until y You los answe attemp 2. Sum the energies from each step and convert to kilojoules Step 1 a. Going from-24.0°C to the melting point of H2O (0 ) is a temperature change of 240°C How much energy is needed to heat 57.0 g of H2O(s) by 240°C if its specific heat is 2.087 J/(g. )? Number eText b. How much energy is needed to melt 57.0 g of H20(s) if its enthalpy of fusion is 333.6 J/g? Help Web c. For H2O, going from the melting point (0°C) to the boiling point (100 °C) is a temperature change of 100°C. How much energy is needed to heat 57.0 g of H20() by 100 if its specific heat is 4.184 J/(g )? Next Previous Give Up & View Solution O Check Answer Exit Tech HintExplanation / Answer
step-1
a. energy needed to heat H2O(s)
Q = m*s*DT
m = mass of ice = 57 g
s = specific heat of ice = 2.087 j/g.c
DT = 0-(-24) = 24 c
Q = 57*2.087*24 = 2855 joule
= 2.855 kj
b. energy needed to convert heat H2O(s) to H2O(l)
Q = m*DHfus
= 57*333.6
= 19.015 kj
c.
energy needed to heat H2O(l) to its boiling point
Q = m*s*DT
m = mass of ice = 57 g
s = specific heat of ice = 4.184 j/g.c
DT = 100-0 = 100 c
Q = 57*4.184*100 = 23.85 kjoule
d. nergy needed to convert heat H2O(l) to H2O(s)
Q = m*DHvap
= 57*2257
= 128.649 kj
e. energy needed to heat H2O(g) to 115 c
Q = m*s*DT
m = mass of water vapor = 57 g
s = specific heat of water vapor = 2.00 j/g.c
DT = 115-100 = 15 c
Q = 57*2*15 = 1710 joule
= 1.71 kj