methyl isocyanate (CH3NC) isomerizes to acetonitrile (CH3CN)

methyl isocyanate (CH3NC) isomerizes to acetonitrile (CH3CN)

 

 

기체 상태에서 메틸 이소시아네이트(CH3NC)는

아세토나이트릴(CH3CN)으로 이성화한다.

25℃에서 ΔH° = –89.5 kJ/mol, ΔG° = –73.8 kJ/mol이다.

100℃에서 이 반응의 평형 상수를 찾아라.

 

 

In the gas phase, methyl isocyanate (CH3NC) isomerizes to acetonitrile (CH3CN),

H3C–N≡C(g) ⇌ H3C–C≡N(g)

with ΔH° = –89.5 kJ/mol and ΔG° = –73.8 kJ/mol at 25℃.

Find the equilibrium constant for this reaction at 100°C.

 

What is the equilibrium constant, Kp, for this reaction at 100℃,

assuming that the enthalpy and entropy of reaction

are independent of temperature.

 

 

 

[참고] CH3NC는

methyl isocyanate가 아니라, methyl isocyanide이다.

 

 

 

From ΔG = ΔH – TΔS

( 참고 https://ywpop.tistory.com/7438 )

 

ΔS = (ΔH – ΔG) / T

= ((–89.5) – (–73.8)) / (273+25)

= –0.0527 kJ/mol•K

---> 25℃ ΔS 값

 

 

 

ΔG = ΔH – TΔS

= (–89.5) – (273+100) (–0.0527)

= –69.8 kJ/mol

---> 100℃ ΔG 값

 

 

 

From ΔG = –RT lnK

( 참고 https://ywpop.tistory.com/10336 )

 

lnK = –ΔG / RT

 

K = e^[–ΔG / RT]

= e^[–(–69800) / ((8.314) (273+100))]

= 5.96×10^9

---> 100℃ 평형상수

 

 

 

답: 5.96×10^9

 

 

 

 

[ 관련 글 https://ywpop.blogspot.com/2024/04/methyl-isocyanate-methyl-isocyanide.html ]

methyl isocyanate와 methyl isocyanide를 혼동하지 말자

 

 

 

 

[키워드] CH3NC CH3CN ΔH° = -89.5 kJ/mol ΔG° = -73.8 kJ/mol 25℃ K 100℃, gas CH3NC CH3CN 25℃ ΔH° = -89.5 kJ/mol ΔG° = -73.8 kJ/mol 100℃ K, CH3NC 루이스 기준, CH3-NC 루이스 기준, CH3NCO 루이스 기준, CH3-NCO 루이스 기준