题目

某无色稀溶液X中，可能含有如表所列离子中的某几种。 阴离子CO32- 、SiO32-、AlO2- 、Cl- 阳离子Al3+、Fe3+、Mg2+、NH4+ 、Na+ 取该溶液适量，向其中加入某试剂Y，产生沉淀的物质的量(n)与加入试剂体积(V)的关系如图所示下列说法正确的是 A．若Y是盐酸，则X中一定含有CO32-、SiO32-、AlO2-和Na+ B．若Y是NaOH溶液，则X中一定含有Al3+、Fe3+、NH4+、Cl- C．若Y是NaOH溶液，则ab段发生反应的离子方程式为：NH4++OH-=NH3↑+H2O D．若Y是NaOH溶液，则X中的Al3+、Mg2+、NH4+ 物质的量之根据所掌握的文化或背景知识，选择正确答案 1.  If you go to Singapore, you have to learn to speak _______ and __________. A. Chinese, Japanese       B. English, French       C. Chinese, English        D. English, Japanese 2. Koalas come from __________. They are very cute.    A. Africa           B. China            C. Japan            D. Australia 3. Pandas are our Chinese treasure. They feed on(主食) __________.    A. bamboo         B. animals           C. meat             D. vegetables 4. Which of the following is Chinese?    A. She has curly hair and blue eyes.     B. She has blond hair and brown eyes.    C. He is tall and has blue eyes.         D. He has black hair and black eyes. 5. When it is winter in China, it is _______ in Australia.    A. hot             B. snowing        C. cold              D. cool