Make Colour-Changing Milk

Find out what happens when you a little milk, food colouring, and a drop of dish detergent.

-- WHAT YOU'LL NEED --

Milk
Dinner plate
Food colouring (red, yellow, green, blue)
Dishwashing soap
Cotton swabs

--STEP 1--

Pour enough milk in the dinner plate to completely cover the bottom to the depth of about 1/4". Allow the milk to settle.

--STEP 2--

Add one drop of each of the four colours of food colouring — red, yellow, blue, and green — to the milk. Keep the drops close together in the center of the plate of milk.

--STEP 3--

Find a clean cotton swab for the next part of the experiment. Predict what will happen when you touch the tip of the cotton swab to the center of the milk. It's important not to stir the mix. Just touch it with the tip of the cotton swab.

--STEP 4--

Now place a drop of liquid dish soap on the other end of the cotton swab. Place the soapy end of the cotton swab back in the middle of the milk and hold it there for 10 to 15 seconds. Look at that burst of color!

--STEP 5--

Add another drop of soap to the tip of the cotton swab and try it again. Experiment with placing the cotton swab at different places in the milk. Notice that the colours in the milk continue to move even when the cotton swab is removed.

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Image Credit: www.sophieplayroom.com