按下列要求书写的化学方程式正确的是A．铁在氧气中燃烧：4Fe + 3O2 2Fe2O3 B．澄清石灰水和盐酸发生中和反应：CaO + 2HCl CaCl2 +H2OC．用碳酸氢钠
(3分)下列实验操作不正确的是________。A．在催化剂存在的条件下，苯和溴水发生反应可生成无色比水重的液体溴苯B．用酸性高锰酸钾溶液检验苯中混有
I’m glad I can take this opportunity to express my deep of your kind help you rendered me. A. enjoyment B. appreciation C. entertainment D.
如图是一个物体的三视图，则此三视图所描述的物体是下列哪个几何体？( )
少数用人单位利用劳动者急于签约或不敢拒绝的心理，逼迫劳动者签下了“生死合同”“卖身合同”等。对此认识正确的是（ ） ①这是无效合同，
Dear editor, Several days ago, I heard that a dear friend of mine had killed herself. I was deep in sorrow by the sudden news. I can't keep calm any longer. 16_____. Life is so precious. If we ca
Try writing with the wrong hand Let yourself daydream Develop your inspiration Discover your hidden talents Record your dreams Stimulate your senses 80. Every night, for about 90 minutes, we drif
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