在常温常压下,将16mLH2、C2H2、CH4的混合气体与足量的O2混合,点燃使之完全燃烧,冷却后发现气体总体积减小了26mL,则原混合气体中CH4为()。A.2mL B.4mL C.8mL D.无法计算 答案:B【试题分析】三种气体燃烧的化学方程式为:2H2 + O2 = 2H2O ΔV2 1 32C2H2 + 5O2→4CO2 + 2H2O ΔV2 5 4 3CH4 + 2O2→CO2 + 2H2O ΔV1 2 1 2由以上可知,In the past 12 months, Taylor Swift ____ her CD Fearless become the year’s bestselling album.A.sawB.was seenC.has been seenD.has seen