The mean radius of a molecule of a certain gas is R=0.1 nm , and the molar mass is 18 gram/mole. If pressure P=1.01x105 Pa and temperature T=300K a) What is the mean free path , λ?
b) If a molecule of the gas has diffused a distance of 12m, what is the number of collisions this molecule has undergone?

Aflask with vinegar in it has a mass of 160 grams. a balloon with baking soda in it has a mass of 40 grams. the balloon is attached to the flask to seal the opening and the vinegar and baking soda mixes. the balloon inflates to a large volume. what will the total mass of the balloon and flask be after the balloon inflates? explain. a) less than 200 grams because the solid baking soda disappears. b) 200 grams, because all the atoms remain in the balloon or flask. c) more than 200 grams because the size of the balloon is so much larger. d) less than 200 grams because gases such as the one in the balloon are lighter than solids and liquids.