【英语时差8,16】活化能，火，燃烧棒（上）

Here’s one you probably never thought to ask about before. You’re in the woods building a campfire. You pile up some dry kindling¹ and light a match. Hold the match under the kindling and, sure enough, the kindling starts burning. Okay, so why is that? You held a burning stick up to a non-burning stick. Why Do You Now Have Two Burning Sticks? The answer is in the nature of fire. If you could look at a flame with super-penetrating vision, you’d see that on an atomic level what you have is the rapid combination of carbon and hydrogen atoms in the wood and oxygen atoms in the air. Given a chance, these atoms will link up to form molecules², such as carbon dioxide and hydrogen dioxide. When this happens, energy is released. That energy causes the light and heat that we see and feel when sitting around a campfire.

1 kindling   

n. 点火, 可燃物 动词kindle的现在分词形式

参考例句：

• There were neat piles of kindling wood against the wall. 墙边整齐地放着几堆引火柴。
• "Coal and kindling all in the shed in the backyard." “煤，劈柴，都在后院小屋里。” 来自汉英文学 - 骆驼祥子

2 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。