This week we're going to make a funky milk kaleidoscope. You're sure to want to show this off to your family and friends, so it's probably best that you work out which kaleidoscope works best, then you can make a big one. Be careful, food coloring can stain your clothes.
What you will need:
PHOTO: CATHERINE THOMAS, TAIPEI TIMES
Several small bowls or pie plates
Different types of milk (whole milk, low fat milk, soy milk etc.)
Food coloring
A bamboo skewer or a toothpick
Dish detergent
Water
Cooking oil
+ Each dish should have at least 3cm of fluid in it. Use a different dish for each fluid. Use milk, low fat milk, soy milk and water. Put a large drop of cooking oil in the center of the water.
+ Line the dishes up so that you can see them all. Now very gently bring the food dye as close to the surface of each of the fluids as possible and put one drop of each color at 12 o'clock, 3 o'clock, 6 o'clock and 9 o'clock. Be very careful not to knock or disturb the samples.
+ Place some dish detergent on a small plate. Dip the skewer in the detergent and very carefully poke the skewer just into the surface in the middle of the first sample. Hold the skewer still and watch.
+ Redip the skewer and repeat in all samples. The reaction will keep on going for up to five minutes. Be patient!
+ Compare and contrast what happens in each case.
+ Choose the best two reactions and repeat the experiment, only this time poke the water with a clean (no detergent) skewer, then follow up with three or four drops of detergent onto the air bubble the skewer leaves.
Don't forget to record what happens in your Science Journal.(catherine Thomas, staff writer)
這週我們要製作一個新奇的牛奶萬花筒。你一定會想要向家人或是朋友炫燿,所以最好先確定哪個萬花筒的效果最棒,然後再做一個大一點的。小心喔!食用色素可能會弄髒你的衣服。
所需材料︰
一些小碗或烤派盤
各式牛奶(全脂牛奶、低脂牛奶、豆漿等)
食用色素
一支竹籤或牙籤
洗碗精
清水
食用油
+ 每個盤子應有至少三公分深的液體在裡面。每種液體都用不同的盤子裝著,有全脂牛奶、低脂牛奶、豆奶和水。在水中間滴入一大滴食用油。
+ 將盤子排列整齊,如此一來,你可以看見全部的盤子。現在輕輕地將食用色素拿到每盤液體的表面,愈靠近愈好,然後各滴一滴在十二點鐘、三點鐘、六點鐘和九點鐘位置。千萬小心,別撞到這些樣本。
+ 在小盤子上放一些洗碗精,將竹籤沾上洗碗精,然後小心地插入第一個樣本的中央。靜握住竹籤並觀察變化。
+ 每個樣本都重複一樣的動作。反應會持續達五分鐘,請耐心觀察。
+ 比較和對照每組發生的變化。
+ 選出反應最佳的兩組並重複該實驗,不過,這次使用乾淨的竹籤(不沾洗碗精)然後插入水中,接著滴上三、四滴洗碗精在竹籤插入後所留下的氣泡上。
別忘了將實驗結果記錄在《科學日誌》中喔。 (翻譯:楊鴻泰)
What's the science? 科學原理
Milk is made up of water (polar), sugars and salts (polar) and fats and lipids (nonpolar). The molecules in dish detergent are also both polar and nonpolar. When you add the detergent to the milk, a "current" is created by the attractions and repulsions between the polar and nonpolar properties of the molecules. The food coloring is moved by this and so you can see a kaleidoscope effect.
牛奶是由水(極性)、糖和鹽(極性),以及脂肪與脂質(非極性)所組成。洗碗精裡含有極性與非極性分子。當你把清潔劑加在牛奶裡時,極性和非極性分子間的相互吸引和排斥作用造成了「流動」。食用色素就是因為這樣移動的,所以你才可以看到萬花筒的效果。
Science Journal 科學日誌
Do you know what milk is made up of? Is oil similar to the fat in milk? What do you know about dish detergent? What do you think might happen if you mix milk and dish detergent?
你知道牛奶的組成成分是什麼嗎?食用油和牛奶的油脂類似嗎?你對洗碗精了解多少?如果將牛奶和洗碗精混合,你覺得可能會發生什麼事?
Further ideas 進階點子
What happens if you add some oil to the milk? How do the colors react? How about replacing the dish detergent with shampoo? Shower gel? Liquid hand soap? Try moving the toothpick around in the samples. What happens? If you like you can save your results by lightly placing a coffee filter on the surface. Lift it off and leave it to dry.
如果把食用油加入牛奶會發生什麼事?顏色會如何變化?如果用洗髮精、沐浴乳、洗手乳取代洗碗精,結果又會怎樣?試著拿牙籤在各樣本中來回攪動,會發生什麼事?如果想把實驗結果保存下來,可以在液體表面輕輕覆上一張咖啡濾紙,之後再將濾紙拿起來風乾即可。
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