Activity 4 - Gas Observations

Why did the balloons get bigger? What was happening at the molecular level?

When the balloons were placed in the bowl, and you turned on the pump they began to get bigger. After the pump was turned off they then deflated. The pump moved the molecules out of the container causing the molecular level to drop. This causes the balloon to expand. Once the pump is turned off and the bowl can fill again with molecules the size of the balloon shrinks back down. The molecules are constantly moving and bouncing around. The more molecules you put into the balloon will cause more bouncing on the surface of the balloon. The less molecules you put into the balloon will cause less bouncing on the surface of the balloon. When you take away the bouncing molecules on the outside of the balloon it causes the balloon to expand.