Question

A mole of an ideal gas at 20 ° C and 1.5 atm is transformed at 45 ° C and 7.5 atm. Find the entropy change at constant pressure and volume.

Answer 1

Answer

Correct option is

D

27.22J.k  

−1

mol  

−1

 

T  

1

​

 

P  

1

​

V  

1

​

 

​

=  

T  

2

​

 

P  

2

​

V  

2

​

 

​

  (Ideal gas law)

T  

1

​

 

T  

2

​

 

​

=  

3

6

​

 

ΔS=2.303×n{C  

p

​

log  

10

​

 

T  

1

​

 

T  

2

​

 

​

+Rlog  

10

​

 

P  

2

​

 

P  

1

​

 

​

}

ΔS=2.303×1{30.96log  

10

​

 

3

6

​

+Rlog  

10

​

 

10

20

​

}

ΔS=27.22J.k  

−1

mol  

−1