春节到了，中国人的DNA动了。

中国人把“春节”也叫做“年”，在中国人的DNA中，跟“年”一起到来的还有美味的饺子，年夜饭的拿手菜，红彤彤的灯笼，喜洋洋的对联，再就是绚烂热闹的烟花了。

身处异国他乡，每年这个时候，学校都会为中国孩子举办烟花秀，让我们在异国也能感受到“年”的热烈氛围。

过年为什么要放烟花？传说中的 “年”是个凶猛的怪兽，新年来临时都会到村里抢劫财物，吞吃孩子。为了吓跑这个怪兽，每当“年”来的时候，村民们就会放起鞭炮和烟花，吓跑怪兽。这个习俗发展到后来，就成了“过年”。

根据史料记载，烟花最早出现在唐朝，由唐朝李畋发明。他用小竹筒装填硝黄并点燃，产生巨大声响以驱鬼辟邪。烟花的真正发展是在宋朝，特别是在北宋宣和年间（1119—1125年），人们除了辞旧迎新在春节燃放烟花爆竹外，每逢重大节日及喜事庆典，都要燃放烟花以示庆贺。

烟花之所以能被人们用来庆贺喜庆，还是因为它不光有响彻天际的声音，更有变幻无穷的颜色和色彩纷呈的图案。为什么烟花能展现出这样的形态呢？那是因为在绚烂烟花的背后，有着与时俱进的化学神奇。

Chinese New Year is around the corner and Spring Festival is carved in our DNA.

The Chinese call the Spring Festival "Nian" (New Year), and ever since ancient times, the arrival of Nian has been accompanied by delicious dumplings, New Year's Eve dinner specialties, red lanterns, joyful couplets, and the splendor of fireworks. 

Being in a foreign country, every year at this time, the school organizes afirework show for Chinese students, so that we can also feel at home.

But why do we Chinese set off fireworks at Chinese New Year? Legend has it that "Nian" is a ferocious beast that comes to the village at the beginning of the New Year to rob and eat the children. In order to scare the beast away, the villagers would set off firecrackers and fireworks to scare the beast away whenever the New Year came. This custom developed into "New Year's Eve."

According to historical records, fireworks first appeared in the Tang Dynasty and were invented by Li Tian of this era. He filled small bamboo tubes with nitrate and ignited them to produce a loud sound to drive away ghosts and evil spirits. But the real development of fireworks was in the Song Dynasty, especially in the Northern Song Dynasty Xuanhe years (1119-1125 years). People set off fireworks in to welcome new birth in the Spring Festival. Now, every major festival and celebrationinclude setting off fireworks.

The reason why fireworks are used by people to celebrate the festivities is not only because the sound resonates through the sky but also because of the changing colors and patterns. Why do fireworks display such patterns? Behind the splendor of fireworks, there is the magic of chemistry that has evolved with the times.

烟花的制作需要多种化学物质，包括黑火药（通常含有硫黄、木炭粉、硝酸钾、氯酸钾等）、发光剂（如金属镁或金属铝的粉末）、发色剂（如某些金属化合物，如氯化锶、氯化铜、氯化钡等）。这些化学物质在烟花燃烧过程中各司其责。

1. What are fireworks made of?

A variety of chemicals are needed to make fireworks, including black powder (usually containing sulfur yellow, charcoal powder, potassium nitrate, potassium chlorate, etc.), luminous agents (such as powdered magnesium metal or aluminum metal), and color-emitting agents (such as certain metal compounds, such as strontium chloride, copper chloride, barium chloride, etc.). Each of these chemicals has its own role in the fireworks burning process.

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当烟花中的药剂被点燃后，金属粉（发光剂）在高温下分解，释放出大量的光能和热能，发出强烈的亮度，形成了烟花的“发光效应”。当某些药剂被点燃后生成的固体和液体残渣会在下一层药剂表面形成一层保护层，阻止进一步的燃烧，产生一亮一熄的脉冲现象时，我们就会看到烟花不仅能发光，还能闪烁。

2. Why do fireworks shine?

When the reagent in the fireworks is ignited, the metal powder (luminescent agent) decomposes at high temperature, releasing a large amount of light and heat energy, emitting a strong brightness, forming the "luminous effect" of the fireworks. When the solid and liquid residue generated after certain agents are ignited, they form a protective layer on the surface of the next layer of agents, preventing further burningand producing a pulse phenomenon. We can see that the fireworks can not only glow, but also flicker.

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烟花药剂燃烧时除了能发光外，还能有不同的颜色。这就是所谓的“焰色效应”。火焰颜色是由各成分间通过化学反应生成了某些原子或分子，以一定的频率振动，呈现一定波长的谱带或谱线，使火焰着色成为有色火焰。使用不同金属就能发出不同颜色的光芒。请看下图：

3.Why do fireworks have colors?

In addition to glowing when the fireworks potion burns, it can also have different colors. This is the so-called "flame color effect." Flame color is generated by the chemical reaction between the components of certain atoms or molecules to a certain frequency vibration, showing a certain wavelength of the spectral band or spectral line, so that the flame coloring becomes colored flame. The use of different metals are able to emit different colors of light. Please see the picture below:

烟花药剂在不同的容器中，被点燃后由燃烧转为爆燃而发出闪光的雷声；有的由于产生的气体从孔中喷出，就发出哨声或笛声；有的能产生类似鸟叫或嗡子声音，这就是烟花的“声响效应”。利用这些“声响效应”可制成如称为筒雷、包雷、嗡子、小鸟、哨子、笛子等部件，再采用这些部件又可以配成许多种大小烟花和空中礼花。

4. Why do fireworks emit sound?

The firework reagents in different containers, after being ignited, from burning to deflagration, emit flashing thunder. Some emit whistles or flutes due to the gas emitted from the holes; some produce sounds similar to bird chirping or 嗡子. This is the "acoustic effect" of fireworks. Using these "sound effects" can be made into parts such as tube thunder, Bao thunder, birds, whistles, flutes and so on, and then using these parts can be matched into many kinds of fireworks, including aerial fireworks.

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烟花的药剂被点燃后除了能产生一定光色外，燃烧后产生的“气动效应”还能喷出许多亮星，利用“喷波”（或拉波），就能制成不同烟花的喷花、射珠、旋转、火箭升空，构成各种花形图案的空中礼花。

硬木炭粉可产生金黄色小星；铁粉可产生钢兰小星；铝粉可产生白色小亮星。在“喷波”的作用下，有金黄色、白色、钢兰色的各种喷花，也有乱窜的蝌蚪游水般的零部件（称为波曲率）以及翻跟头的部件（称为绣球）等等，把这些零部件组合后，让我们看到形态各异的烟花形象。

5. Why do fireworks have shapes?

When the fireworks agent is ignited, it produces a certain light color. After burning, the "pneumatic effect" can also spray many bright stars. The use of "spray wave" (or pull the wave), can be made of different fireworks sprays, shooting beads, rotating, and rockets into the air, constituting a variety of flower-shaped patterns.

Hardwood charcoal powder can produce golden yellow stars; iron powder can produce steel blue stars; aluminum powder can produce white stars. Under the action of "spray wave," there are various kinds of golden yellow, white, and steel orchid color spray flowers. There are also scurrying tadpoles-like swimming parts (called wave curvature), as well as somersaulting parts (called the hydrangea) and so on.After combining these parts, we can see the image of the fireworks of different shapes and sizes.

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烟花药剂燃烧时能产生发光、焰色、声响和气动效应外，还有“发烟效应”。在含有氧化剂、可燃剂和有机染料的烟花药剂中，由于燃烧时氧化剂和可燃剂反应放出热量，使有机染料直接升华成蒸气，并在大气中冷凝成为有色烟，利用“发烟效应”可以利用不同的化学成分，可以制成各种颜色的烟云：加入酞青兰可获得蓝色烟，加入碱性嫩黄可获得黄色烟，加入烟雾红可获得红色烟，加入槐黄和次甲兰可获得绿色烟。

6. Why do fireworks emit smoke?

Fireworks’ chemical combustion can produce light, flame color, sound and aerodynamic effects. But there is also a "smoke effect." Fireworks agents containoxidants, combustibles, and organic dyes. The combustion of oxidants and combustibles react to release heat, so that organic dyes directly sublimated into vaporand condense in the atmosphere, creating colored smoke. The use of the "smoke effect" makes use of different chemical components, and can be made into a variety of colors of the smoke cloud: adding phthalocyanine can create blue smoke, add alkaline yellow to get yellow smoke, add smoke red can get red smoke, and acacia yellow and second methyl orchid can lead to green smoke.

随着化学科学的发展，人类展开丰富的想象力，利用化学作用原理和不同化学成分的特性，设计制造出更加色彩斑斓、形态各异的烟花，让节日的气氛更加热烈，让喜庆的心情更加愉悦！

   With the development of chemical science, mankind unfolds its rich imagination using the principle of chemical action and the characteristics of different chemical components. Design and manufacture continues to become more colorfulwithin different forms of fireworks, so that the atmosphere of the festival is more enthusiastic!