本题目来源于试卷: What Drives Chemical Reactions D.2 Energy Cycles in Reactions，类别为 IB化学
[单选题]
Using the table below, choose the correct expression that t4 um n;ffj-nxxtp:97represena*.ly :b+ts3p fgj+z wts the enthalpy change for the follo3*f t:w.zj+sglaybp+ wing hydrogenation reaction:
$C_2H_4$(g)+$H_2$(g)→$C_2H_6$(g)
Substance is $C_2H_4$(g) ; ΔH (Enthalpy of Formation) kJ mol$^{-1}$ is x
Substance is $C_2H_6$(g) ; ΔH (Enthalpy of Formation) kJ mol$^{-1}$ is y
A. −x+y kJ mol${-1}$
B. x+y kJ mol${-1}$
C. −2x+y kJ mol${-1}$
D. −2x−2y kJ mol${-1}$
参考答案: A
本题详细解析:
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