Moles and Particles How many moles are in 4.65 x water molecules? Starting quantity? Particles Ending quantity? Moles Conversion factor: 1 mole = 6.02 x water molecules Want to replace particles with moles
Moles and Particles 4.65 x water molecules ÷ 6.02 x water molecules per mole = moles water
Moles and Mass How many moles are in 25.8 g water? Starting quantity? Mass Ending quantity? Moles Conversion factor: 1 mole water = 18.0 g water (molecular weight of water) Want to replace mass with moles
Moles and Mass 25.8 g water ÷ 18.0 g water per mole water = 1.43 moles water
Moles and Volume How many moles are in L of water vapor at STP? Starting quantity? Volume Ending quantity? Moles Conversion factor: 1 mole water vapor = 22.4 L water vapor at STP Want to replace volume with moles
Moles and Volume L water vapor ÷ 22.4 L water vapor per mole water vapor = moles water
Thought Questions What do you notice about the conversion factors in the past three problems? What do you think you would do with these conversion factors if you started with moles? What do you think you would do if your starting and ending quantities were mass and volume? Mass and number of particles? Volume and number of particles?
Group Work Get into groups of 3-4 Grab one sheet of paper and some markers for each group Work on your assigned problem for 5 minutes – feel free to make it as colorful as possible to show each quantity (moles, mass, volume, number of particles) Present your solution to the class