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[2012·江门第二次调研]有关能量的判断或表示方法正确的是(   )

A:由:H+(aq)+OH(aq)=H2O(l)H=-57.3kJ/mol,可知:含1mol CH3COOH的溶液与含1mol NaOH的溶液混合,放出热量等于57.3 kJ

B:从C(石墨)=C(金刚石)H=+1.9kJ/mol,可知石墨比金刚石更稳定

C:等质量的硫蒸气和硫固体分别完全燃烧,后者放出热量更多

D:2gH2完全燃烧生成液态水放出285.8kJ热量,则氢气燃烧的热化学方程式为:2H2(g)+O2(g)=2 H2O(l)H=-285.8kJ/mol

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B

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