按要求改写句子。

1. His pen is on the desk. (就画线部分提问)

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2. Li Ming has some interesting books. (改为一般疑问句)

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3. Tom does his homework every day. (改为否定句)

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4. This is an apple tree. (改为复数句子)

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5. every, watch, they, TV, day (连词成句)

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早在1722年，法国化学家拉瓦锡进行了燃烧金刚石的试验．他将金刚石放置在玻璃灯罩里，用放大镜把日光聚焦在金刚石上，使金刚石燃烧，得到无色气体．将该气体通入澄清石灰水，得到白色的碳酸钙沉淀．写出上述反应的化学方程式：______；______．