This week in Science we have been conducting an experiment to find out if ‘gases’ weigh. We bought some fizzy pop and identified that the gas which gives the fizz and bubbles is Carbon Dioxide. We made a prediction that it is just a type of gas and therefore doesn’t weigh. To find out if we were correct we shook the gas out of the drink, left it overnight with the lid off and kept weighing it. To our astonishment the weight of the bottle at the end of the week was much lighter. We concluded that therefore that gas must weigh!