17.在298 K时,C2H4(g)、H2(g)、C2H6(g)的标准摩尔燃烧焓△H0"分别为 -1411-|||-x^1 -285.8kJcdot mo(l)^-1,-1560kJcdot mo(r)^-1 则反应 _(2)(H)_(4)(g)+(H)_(2)(g)=(C)_(2)(H)_((()) 的Delta (A)_(n)^9-|||-A. -136.8kJcdot mo(l)^-1 B..8kJcdot mo(l)^1-|||-times 1-mo(l)^-1 D.cdot mo(l)^1