Year 4 wanted to find out if gas has any weight. To begin with, they weighed a glass of lemonade using digital scales. After that, they stirred it for 10 minutes until all of the bubbles had disappeared. Finally, they weighed the glass of lemonade again and observed the difference in weight. They noticed that there was a slight decrease in weight which allowed them to conclude that the gas in lemonade, carbon dioxide, weighs a small amount.