In science we have been doing the coke and Mentos experiment. For the first one we did a bottle of coke and we put one Mentos in it and it went 1.5m high and it took about 6mins to stop bubbleing . And we did a few more after with 4 and 7 Mentos especially in a bottle and four out that the more mentoses you put in the higher it will go and the time for the bubbles going down lowers,but with the less mentos put in the bottle it will take a lower time to stop bubbling and it will go not as high as the bottles with the more mentos. We have been studying on how the experiment work and what the surface of the Mentos is,the surface of the Mentos is like the moon rough and it has little craters in it.
http://science.howstuffworks.com/innovation/37005-mythbusters-diet-coke-and-mentos-video.htm
