题目

（1）人类认识原子结构的历史经历了以下几个阶段，请填写下表：发展阶段主要化学家主要贡献（1）道尔顿（Dalton） （2） 葡萄干面包模型（3）卢瑟福（Rutherford） （4）波尔（Bohr）现代原子论（2）19世纪末20世纪初证明原子的可分性和具有更复杂结构的重要科学发现与现象是 和（3）1911年，新西兰出身的美国物理学家卢瑟福用а射线轰击极薄的金箔片，他惊奇地发现，过去一直是认为原子是“实心球”，而由这种“实心球”紧密排列而成的金箔，竟Dear Tom ,I've finally made up my mind to go to America for farther study after graduation. I've been longed to go to America,mainly for two reasons. One is that I want to experience American culture,which is believed to have the most diverse in the world,and the another is that I hope to broaden my horizon in this developed country. But to telling you the truth,I have some worries about this. I don't have good command of English,especially spoken English,so Fm afraid Fll have difficulty fitting very soon. Besides,I may suffer from highly pressure from college courses,which I'm not sure I can handle with.With so many things bother me,I hope you can offer me some practical advices. Looking forward to your reply.Yours,Li Hua