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- postmortem chemical change 死后化学变化
- We saw that a chemical change had taken place. 我们看到已发生了化学变化。
- A chemical change takes place in any substance when it burns. 物质燃烧时产生化学变化。
- Microorganisms are the agents that bring about the chemical change. 微生物是引起化学变化的作用者。
- This chemical change can be expressed by an equation. 我们可用反应式表示这种化学变化。
- These are physical changes while those are chemical changes. 这些是物理变化而那些是化学变化。
- New material can be brought about through chemical change. 通过化学变化可以生成新的物质。
- Heat and light can be given off by this chemical change. 这种化学反应能放出热和光。
- A chemical change takes place in paper when it burns. 纸燃烧时产生化学反应。
- Sun, air and wind cause quick chemical changes. 太阳、空气和风引起快速的化学变化。
- A chemical change always results in forming at least on new substance. 一种化学变化总是产生至少一种新物质。
- A chemical change has to take place before the energy can be let loose. 能量释放，必须有化学变化。
- Any change that results in forming a new substance is a chemical change. 导致一种新物质生成的任何变化是化学变化。
- Whenever a chemical change takes place ,There is a new substance formed . 每当发生化学变化时，就有一种新的物质生成。
- Whenever a chemical change takes place,there is a new conference to formed. 每当发生化学变化，就有一种新的物质生成。
- A solid takes part in chemical change in so far as it dissolves or volatilizes. 就这门课程涉及工程学各部门的一般知识而论，它是一门很难的课程。
- When a chemical change takes place, one or more substances are formed. 当化学变化发生时,就形成了一种或多种物质。
- Some kinds of acids react on metals to cause chemical changes. 有几种酸对金属起作用，会引起化学变化。
- Coal was formed out of dead forests by a long slow process of chemical change. 煤是由埋在地底的森林经过长期而缓慢的化学变化过程而形成的。
- Whenever a chemical change takes place , There is a new substance formed . 每当发生化学变化时，就有一种新的物质生成。
