英語(yǔ)聽力文摘 可樂的神奇清潔能力
飲料的神奇清潔能力
Let’s begin with a cleaning tip: If you have some tarnished or corroded brass that you want to clean, an old brass candlestick for example, you can use Coca-Cola, or any other cola soft drink, and that brass will come clean.
How Does This Work?
And if Cola is such an effective cleaner of corroded metal , what is it doing to the inside of your stomach?
Cola cleans brass because it’s mildly acidic.
Here’s what happens: When brass or another metal alloy becomes tarnished, this means that there has been a chemical reaction between the oxygen in the air and one of the metals in the alloy.
Oxygen atoms combine with metal atoms to form what’s called an oxide, and this oxide is what makes the metal appear tarnished. Acids, like the weak acid present in your can of Coke, can react with oxides to effectively reverse the process of tarnishing. The acid dissolves the metal oxides that make the tarnish, leaving only shiny metal behind.
Try It At Home!
You can try this at home, even if you don’t have a brass candlestick. Leave a tarnished old penny in a glass of cola overnight. In the morning it will be shiny and fresh.
Your Stomach And Acid
If the acid in cola is so good at attacking tarnished metal, what might it do to your insides? Actually, your stomach already contains its own supply of acid which it uses to digest food.
This stomach acid is a great deal stronger than the acid in a can of Coke. Indeed, stomach acid would be an even better tarnish remover than cola!
有個(gè)去污點(diǎn)子：如果你想要清除銅銹，例如銅燭臺(tái)，可以使用可口可樂或者其它可樂飲料，清洗后的燭臺(tái)光亮如新。
飲料是如何清潔的呢?
如果可樂能有效清潔金屬銹斑，那么可樂對(duì)人體的胃會(huì)產(chǎn)生什么影響呢?
可樂能清潔銅銹是因?yàn)榭蓸烦嗜跛嵝浴?/p>
銅或其它金屬合金生銹是因?yàn)榭諝庵械难鯕夂秃辖鹬械哪撤N金屬發(fā)生了化學(xué)反應(yīng)。
氧原子結(jié)合了金屬原子，形成所謂的氧化物。氧化物就是金屬銹。而酸，比如可樂中的弱酸，和氧化物產(chǎn)生化學(xué)反應(yīng)，能有效避免生銹。酸可以分解金屬氧化物，化學(xué)反應(yīng)后的金屬锃亮。
在家試驗(yàn)
即便家里沒有銅燭臺(tái)，你可以做這樣的試驗(yàn)：晚上，將一枚舊硬幣丟進(jìn)裝有可樂的杯里。第二天早上，硬幣就變得閃亮如新。
酸對(duì)人體胃的影響
如果可樂能有效清潔金屬銹斑，那么可樂對(duì)人體的內(nèi)臟會(huì)產(chǎn)生什么影響呢?事實(shí)上，人體的胃里就有分泌的酸液來消化食物。
胃酸的酸性比一聽可樂還強(qiáng)。說真的，胃酸甚至比可樂更能除銹。
