時差N小時:你能讓無糖可樂浮起來嗎?

Here's an at-home experiment you can try.

你可以在家做這樣的實驗。

Take a can of “classic” Coca-Cola and a can of DietCoke, andwithout opening either one submergethem in water.

把沒打開過的兩聽可樂放在深槽或者高桶中，

A deepsink or a bucket will do the trick.

里面的水淹沒兩聽可樂，

You'll find the can of Diet Coke rises to the top, whilethe ClassicCoke stays sunk.Can you guess why?Why?

你會發(fā)現(xiàn)無糖可樂浮在水面;而含糖可樂卻沉下去了。你能猜到原因嗎?

The answer lies in the chemical contents of the Diet Coke-in fact, in the very distinctionthatmakes it “Diet”.

奧秘就在于無糖可樂的成分，這也是“無糖”的原因。

Although their ingredients are otherwise similar, Diet Coke is not made with real sugar: instead,themakers of Coca-Cola products have replaced the sugar with a synthetic chemical calledAspartame.

雖然，無糖可樂和普通可樂的成分很相似，無糖可樂中添加的并非真正的糖，而是一種做“阿斯巴甜”的合成化學(xué)物。

Aspartame, which is commonly known as Nutrasweet, is a kind of substitute sugar-intendedtomimic the distinctive taste of sugar without carrying the associated calories.

“阿斯巴甜”是一種常見的代糖甜味劑，不含糖的熱量卻有糖的甜味。

Real sugar has a high molecular density.

真正的糖分子密度高，

In other words you can think of sugar molecules as beingthickly packed together.

也就是說糖分子緊密地排列在一起。

This also means sugar molecules themselves will be relatively heavy, even when dissolvedinsolution.

即使溶解在溶液中，相同體積的糖更重。

In the case of the sinking Coke, the real sugar content is acting as an anchor for the can.

實驗中沉下去的普通可樂，正是因為糖成分像錨般讓罐子下沉。

There's also the fact that Nutrasweet is much sweeter than sugar, and so less is needed per cantoachieve that recognizable Coca-Cola taste.

代糖比糖甜，所以更少的代糖能達(dá)到普通可樂的甜味。

Thus the bobbing Diet Coke not only has a loweraverage density, it also has a lower mass-there's less “stuff” dissolved in the mixture.

這樣水中搖擺的無糖可樂不僅平均密度更低，質(zhì)量也比普通可樂輕-因為更少的代糖溶解在可樂中。

If you werean advertising executive, you might want to market diet sodas as “Light”-itwouldn't be far fromthe truth.

如果你是廣告商，你可以這樣宣傳-無糖碳酸飲料的優(yōu)點：輕。這可沒有說大話。