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来源:学生作业帮助网 编辑:作业帮 时间:2024/03/29 18:59:22
一天7700吨生活污水的河道怎么治理?已启用水生植物和曝气设备,一天8000吨居民生活污水,河道长1000米宽8米,无生态护坡,污水管道密布 生物质电厂飞灰排入河道会对环境造成影响吗?什么影响? 当地壳抬升时,不考虑气候影响,快速抬升和慢速抬升对河流的状况分别有何影响 8k纸张是多大?如何计算纸张的大小? I paid him a visit. I( ) a.visited him b.made him visit c.did him a visit d.paid for a visit the president paid—— a visit to China.A four days B four-day C four-days D four-days’ President Bush,为什么President在前? 铅蓄电池:Pb+PbO2+2H2SO4=2PbSO4+2H2O(1)写出电极反应式(2)电解H2SO4浓度怎么变化?(3)当通过1mol电子,负极增重多少克 Do you go to the cinema e( ) Saturday and Sunday?写出句中所缺单词 生活污水系统组成部分及各部分的作用有哪些? 放电时,正极反应为:PbO2 + 4H+ + SO42- + 2e- = PbSO4 + 2H2O.这是铅蓄电池的电极反应,为什么有的地方在化学式后面要标明物质的状态呢 I am afraid that you have to ____ your optimistic views in light of the tragic news that has justjust arrived.请问空格处是用alter吗?为什么? PbO2 + 4H+ + SO42- + 2e- = PbSO4 + 2H2O ___ you ever ___ of this news that Jack will come to China next month?(hear) PbO2 + 2e- + SO42 + 4H+ = PbSO4 + 2H2O假如左边的2e和SO4根以及H离子中和了 那么PbO2降为PbSO4时的电子从哪来? The news has just ____ that the Queen is going to have a baby next March. the news______the leaders are coming next week______not ture.a.that is B.which is为什么选that,而不选which呢 ___ you___(go) to the most beautiful cinema last night? 地理环境对人类活动方面有哪些影响? 铅蓄电池是化学能源,工作时电池总反应为PbO2+Pb+2H2SO4=2PbSO4+2H2O.实验室用铅蓄电池做电源电解饱和食盐水制取氯气,今若制得Cl20.05mol,这时电池内消耗的H2SO4的物质的量至少是( ) 英语翻译I have been to Beijing,Xi'an,Dalian,Tianjing,Hangzhou,Jilan.I like then all.I always have a wonderful time when I travel in China. 化学问题铅蓄电池总反应为pbo2+pb+2H2SO4===2pbSO4+2H2O铅蓄电池总反应为pbo2+pb+2H2SO4===2pbSO4+2H2O请问正极反应是? 铅蓄电池的两极分别为Pb、PbO2,电解质溶液为硫酸溶液,工作时的反应为Pb+PbO2+2H2SO4=2PbSO4+2H2O,下列结论正确的是()  A.Pb为正极被氧化B.溶液的PH值不断减小  C.SO42-只向PbO2处移动 D. 衣服染料的原料成分中有没有植物油的成分 how was your vacation in Japan?(改为同义句)...________ was your vacation in Japan ________? how was your vacation 同义转换要原因哦 请根据对联的相关知识,以节约用水为内容完成下面这幅对联 上联:下联:生态和谐决定国家振兴请根据对联的相关知识,以节约用水为内容完成下面这幅对联上联:下联:生态和谐决定国家 How was your vacation in Thailand(改同义句)—— was your vacation in Thailand——? 如何煎鱼不粘锅? 这是什么东西? 怎样煎鱼不粘锅? 这个烫发叫什么名?