“金属明星”钛的获取方法之一为：TiCl₄＋2Mg　$\underset{=}{△}$2MgCl₂＋Ti，该反应属于

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                                                                                                      刘方平 
                                                                                    更深月色半人家，北斗阑干南斗斜。
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