열용량과 비열. 1.02 g C18H36O2 4.26℃ 9.43 kJ/℃

열용량과 비열. 1.02 g C18H36O2 4.26℃ 9.43 kJ/℃

 

 

When 1.02 g of steric acid, C18H36O2,

was burned completely in a bomb calorimeter,

the temperature of the calorimeter rose by 4.26°C.

The heat capacity of the calorimeter was 9.43 kJ/°C.

Calculate the total heat of combustion of steric acid in kJ/mol.

 

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q = C Δt

( 참고 https://ywpop.tistory.com/2897 )

 

= (9.43 kJ/°C) (4.26°C)

= 40.17 kJ

---> 열량계가 흡수한 열이므로,

1.02 g steric acid가 방출한 열 = -40.17 kJ

 

 

 

C18H36O2의 몰질량 = 284.48 g/mol 이므로,

1.02 g / (284.48 g/mol) = 0.003585 mol C18H36O2

( 참고 https://ywpop.tistory.com/7738 )

 

 

 

몰당 kJ을 계산하면,

-40.17 kJ / 0.003585 mol

= -11205 kJ/mol

 

 

 

답: -1.12×10^4 kJ/mol