普九义务教材通用教案设计精编 中学卷中学思想

的稳定性。③钠熔化成小球后，小球为什么可在水面上向任意方向游动？④你能推断出钠与水反应的化学方程式，并说明反应发生的原因吗？⑤你能归纳出钠的化学性质吗？这样，通过阅读教材，实验讨论，让学生自己通过分析、判断、推理，使所学知识由感性到理性，由个别到一般；最后得出结论。这一阶段大约需10 分钟。4 ．归纳小结实验、看书、讨论后，教师应不失时机地进行简明扼要的小结。根据钠的化学性质，引导学生推断出钠的存在形式、贮存、用途及制法，进一步加深学生对物质结构决定性质，性质决定其存在、用途、制法这一规律的理解。归纳小结约需8 分钟。5 ．练习巩固将已写好练习题的小黑板挂出，要求学生在8 分钟内完成，教师用剩余时间检查完成情况。为了提高“四环节教学法”的教学效果，我们还采取适当增加实验内容，改进实验方法，以提高实验的效果；也可将部分演示实验及大部分学生实验改为学生课堂实验，并精心安排教学过程，采用灵活多样的教学方式进行教学。如“胶体”一节，理论性强，实验内容多，教师觉得难教。我们采用“四环节教学法”教学时，在不增加课时的同时，将演示实验和学生实验合二为一，改为学生课堂实验，并调整了教材内容的先后次序：第一节课为实验课。指导学生完成教材中的“胶体的制备”、“渗析”、“丁达尔现象”、“胶体的凝聚”等实验，还增加了淀粉胶体的制备，溶液、浊液、胶体的区别等实验。课后教师布置阅读提纲，要求学生根据实验现象认真阅读教材。第二课时，归纳小结。结合溶液、浊液、胶体三种分散系，教师设计了二十多个What is the colour of the tigers eyes? 3.The question is often asked:Just what do we communists mean when we say —socialism? Its not complicated. We mean an advanced stage of social development which will abolish private ownership of the means of production.The means of production are today the propert of a small group of capitalists.They use their property to exploi the labour of millions for their own personal profit. By socialism we mean collective o nership by the whole people of all the socially necessary means of production(land, natural resources,industries, railroads, banks,communications,etc.). We mean the operation of these means of production through a planned economy which will guarantee an ample supply and distribution of allcommodities and services to all the people. Socialism does not exclude private owner hip of personal property; in fact,most of us would have far more under socialism than we have now.Socialism denies the right to use any savings or possessions to exploit the labour of others.Under socialism, work is the right and duty of all able-bodies in accordance with the concept , He who does not work-neither shall he eat. a.Name three of the socially necessary means of production mentioned in this paragraph. b.Under socialism would we have more or less property than we have now? c.Under socialism what is the righ