Styrofoam melt in acetone

Hi all, have you seen styrofoam melts in acetone (a common component found in nail polish remover). This is an endothermic reaction. Once styrofoam add into the acetone it will melt to become a semi-solid foam. When the acetone is poured away, the semi-solid foam will harden. I have tried it myself as the video taken is not so good, so I did not add it in. Anyway the video is easily available in the net.

Regarding how it melts the styrofoam, I am still not sure. Once I know it, I will put it up in our company newsletter.

Adding Mentos to Coke

Hi I think most of you have seen this in the internet. However did you do it yourself physically to see how vigorous the reaction is? S0 this exciting experiment definitely have to add it into my blog. Actually this experiment is request by one of the chemistry teacher. He is testing the student to see whether this is a physical or chemical reaction and tell them to go back and search in the internet to explain why this reaction occurs. That's why you see the teacher demonstrating and the student is watching by the side. Sorry about the orientation of the video as I do not know how to edit and rotate it.

Anyway why this reaction will occurs? This is due to the carbon dioxide gas that is pumped in the factory. Normally the gas in soft drink stay suspended in the liquid and cannot expand to form more bubbles.

This is because water molecules strongly attract each other, linking together to form a tight mesh around each bubble of carbon dioxide gas in the soda. In order to form a new bubble, or even to expand a bubble that has already formed, water molecules must push away from each other. It takes extra energy to break this "surface tension." In other words, water "resists" the expansion of bubbles in the soda.

When Mentos is dropped into the coke, the gelatin and gum arabic from the dissolving candy break the surface tension. This disrupts the water mesh, so that it takes less work to expand and form new bubbles. Each Mentos candy has thousands of tiny pits all over the surface. These tiny pits are called nucleation sites - perfect places for carbon dioxide bubbles to form. As soon as the Mentos hit the soda, bubbles form all over the surface of the candy.

When all this gas is released, it literally pushes all of the liquid up and out of the bottle in an incredible soda blast.