ADVANCED HONORS CHEMISTRY - CHAPTER 17 NAME:

THERMOCHEMISTRY DATE:

TEXTBK - STANDARDIZED TEST PREP - ANS - V3 PAGE #:

1. A

2. C

3. A

4. C

5. C

6. - 3.98 x 103 kJ

7. 0.33 kJ

8. 23.3 kJ

9. Region B: 13.1 kJ

Region C: 35.2 kJ

10. Note: The formula for benzene is C6H6 and its Molar Mass =

78.1 gmol

Region A:

ΔHMelting the Benzene = molesBenzene( ) ΔHMolar Heat of Fusion of Benzene( )  

 

ΔHMelting the Benzene = 1 mol benzene( ) 9.87 kJ

mol benzene"

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ΔHMelting the Benzene = 9.87 kJ

Region B:

ΔHHeating the Benzene = massBenzene( ) ΔTBenzene( ) sBenzene( )  

ΔHHeating the Benzene = massBenzene( ) TBoiling the Benzene - TMelting the Benzene( ) sBenzene( )  

 

Since Δ oC = ΔK  

 

1.74 Jg( ) oC( )

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= 1.74 Jg( ) K( )

!

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ΔHHeating the Benzene = 78.1 g( ) 353.3 K - 278.7 K( ) 1.74 J

g( ) K( )"

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%

&'  

 

ΔHHeating the Benzene = 78.1 g( ) 74.6 K( ) 1.74 J

g( ) K( )"

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%

&'  

 

ΔHHeating the Benzene = 10,138 J  

 

ΔHHeating the Benzene = 101 kJ  

 

Region C:

ΔHBoiling the Benzene = molesBenzene( ) ΔHMolar Heat of Vaporization of Benzene( )  

 

ΔHBoiling the Benzene = 1 mol benzene( ) 30.8 kJ

mol benzene"

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&'  

ΔHBoiling the Benzene = 30.8 kJ