题目

已知有反应2NO+O2==2NO2。今在体积为VL的密闭容器中通入amolNO和bmolO2。反应后容器中的氮原子和氧原子的原子个数之比是                (    ) A. a/b        B. a/2b        C. a/(a+2b)     D. a/(2a+2b)  答案：C解析:略 —I ______ something wrong just now. May 1 use your eraser?—Of course. Here you are.A. write B. wrote C. am writing