Consider
the melting of one mole of water. Use the following data to answer the
questions:S?=(
H2O,...

Question

Consider
the melting of one mole of water. Use the following data to answer the
questions:S?=(
H2O, l)=69.9J/K.mol, S?( H2O,
s)=47.8J/K.mol, ?H?( H2O, l)=-285.8kJ/mol, and ?H?( H2O,
s)=-298.8kJ/mol. Assume standard molar entropies and enthalpies of formation are not functions of temperature in this
range. a) calculate the entropy change of the system for melting ice at -5?C.
b) Calculate the entropy change of the surrounding for melting ice at -5?Cand C) Is this reaction spontaneous at -5?C?
Justify.
next:

The
heat capacity is critical in calculating the enthalpy and entropy. Using the
data (heat capacity) from book or internet and also?fusH (I2)
= 15.52387kJ/mol at 387K and?vap
(I2) =41.57kJ/mol at 457K.a) Calculate the heat required to bring one
mole of iodine from 0K to 500k. b) calculate the absolute entropyof iodine at 500K

Robert · Accepted Answer

Problem 1 
Given data is 
 
 
 
 
o 1
f 2
o 1
f 2
o 1 1
2
o 1 1
2
H H O( ) 285.8KJmol
H H O(s) 298.8KJmol
S H O( ) 69.9JK mol
S H O(s) 47.8JK mol


 
 
  
  


 
The entropy change of the system of ice melting o@ 5 C  is given by  
   o o osystem 2 2S S H O( ) S H O(s)
69.9 47.8
22.1J
  
 

 
Now, the change in the entropy of the surrounding is given by 
  
o
systemo
surrounding
3
3
1 1
H
S
T
285.8 298.8 x10
268.15
13x10
268.15
48.48JK mol 

  
  
 
 
 
 
Hence, the change in entropy of the universe is  
o o o
universe system surrounding
1 1
1 1
S S S
(22.1 48.48) JK mol
26.38JK mol
 
 
   
 
 

Since ouniverseS 0  , the transition of ice to water 
o
@ 5 C   (or melting) is not a spontaneous process.

Consider the melting of one mole of water. Use the following data to answer the questions:S ? =( H 2 O, l)=69.9J/K.mol, S ? ( H 2 O, s)=47.8J/K.mol, ?H?( H 2 O, l)=-285.8kJ/mol, and ?H?( H 2...

Solution

Answer To This Question Is Available To Download

Related Questions & Answers

Submit New Assignment