1. Gas Has Mass uDu Task: Find the mass of air in a balloon. Materials: Balloon (1) Balance (1) Tape (5 cm) SCORING: 5 points 1 st group with correct answer 10 points. If method is NOT acceptable, 4 points !!! 2 nd … 9 points …

2. Gas Has Mass uDu FOLLOWUP: If the air in a balloon weighs a couple of grams, how much does the atmosphere weigh?

3. Gas Has Mass uDu FOLLOWUP: If the air in a balloon weighs a couple of grams, how much does the atmosphere weigh? 5.3 x 10 18 kg (12 x 10 18 pounds) — a lot, but only about a millionth of the total mass of the Earth. Let’s demonstrate …

4. Gas Has Mass uDu FOLLOWUP: Evangelista Torricelli (6/11/1644): "Noi viviamo sommersi nel fundo d'un pelago d'aria" “We live submerged at the bottom of an ocean of air” (which he thought was 50 miles high.)