【单选题】I was _______ at the letter, which was________ to my classmates.
【单选题】有H2和N2的混合气体50mL,加空气燃烧后,体积减少15mL,则H2在混合气体中的体积百分含量为( )。
【判断题】含有 N 2 和 H 2 的混合气体中 N 2 的分 体积 V (N 2 ) = n (N 2 ) R T / p ( 总 ) 。
【简答题】I remember my maths teacher Mr Young very well. He stood out because the kids made fun of him. He was missing one of his fingers. In school Maths was my worst subject. I don’t think there was ever a d...
【简答题】My favorite physicist (物理学家) is Qian Xuesen. He was born in Shanghai on December 11, 1911. He was a little fat and of medium height. And his eyes were wise. He liked music, art and science (科学). He st...
【单选题】有H2和N2的混合气体50mL,加空气燃烧后,体积减小15mL,则H2在混合气体中的体积百分含量为()。
【判断题】含有 N 2 和 H 2 的混合气体中, N 2 的分体积 V (N 2 )= n (N 2 ) RT / p ( 总 ) 。 ( )
【简答题】Liu Kai is my classmate. He is a good student and always ready to help the others. One day on his way school, he saw a little girl crosses the road. A car was coming towards to her quickly and the gir...
【单选题】有H2和N2的混合气体50mL,加空气燃烧后,体积减少15mL,则H2在混合气体中的体积百分含量为()。