1.通过实验激发学生的学习兴趣。学生的学习兴趣如何,对教学效果影响很大。如要检验氧气,不直接介绍氧气的检验方法,而是先做这样一组演示实验:取三只盖着玻璃片的集气瓶,告诉学生瓶中依次分别装有空气、二氧化碳气和氧气,然后用燃着的木条先后插入其中,现象明显不同,燃着的木条,插入盛空气的瓶中看不出变化;插入盛二氧化碳气的瓶中火立刻熄灭;插入成氧气的瓶中火烧得更旺。这些现象不但激起了学生的浓厚兴趣,而 1. Through experiments to stimulate students’ interest in learning. Students interest in learning, a great impact on teaching effectiveness. If you want to test oxygen, do not directly introduce the test method of oxygen, but to do such a demonstration experiment: Take three glass-covered gas collection bottle, told the students in turn were filled with air, carbon dioxide gas and oxygen, And then with a burning stick inserted one after another, the phenomenon was significantly different, burning wood, inserted into the air bottle can not see the change; inserted into the bottle of carbon dioxide gas immediately extinguished the fire; inserted into a bottle of oxygen fire More flourishing. These phenomena not only aroused the students’ interest, however