1. Stoichiometry

2. The Mole What is a mole?

3. No not this type of mole either

4. The Mole Chemists use a measurement called ‘the mole’ A mole is like a dozen eggs= 12 eggs or a pair of shoes= 2 shoes However, the mole is a very large number  This is because atoms are so small that chemists need a lot to be able to find their mass

5. How big is the mole?? A mole contains 6.023 x 10 23 of anything  6.023 x 10 23 is a.k.a AVOGADRO’S NUMBER How big is a mole exactly?  If you could count 10 million numbers every second, it would take you 2 billion years to count an avogadro’s number out  If you had a mole of unpopped popcorn kernals it would cover the entire planet to a depth of 9 miles  If you poured out a mole number of cans of pop out you would cover the entire earth with an ocean of pop 200 miles deep

6. Therefore, 1 mole= 6.023 x 10 23 particles or 6.023 x 10 23 particles/mol 1 mole Cl= 6.023 x 10 23 particles 1 mole of H= 6.023 x 10 23 particles 2 moles=

7. Atomic Molar Mass The mass (in grams) of 1 mole of a given element To find this for each element you must look at the periodic table:  1 mole of C= 12 g (or 12g/mol)  What is the mass of 1 mole of oxygen?  What about 2 moles of oxygen?  3 moles?

8. Molecular Molar Mass Is the mass (in grams) of all the elements in the molecule To find the mass: 1. find each element’s atomic mass and 2. add all of the atomic masses together Ex NaOH:  Na= 1 x 23 g/mol  O= 1x 16 g/mol  H= 1 x 1g/mol 40 g/mol of NaOH

9. Ex H2O Ex. H2SO4

10. Find the following masses MgBr2, Ga(NO2)3, CrI2, BeSO4 Assignment: molar mass worksheet

11. Stoichiometery Given two out of these three values for mass, moles and/or molar mass, you can figure out the value of the missing value Mass= moles x molar mass Moles= mass/molar mass Molar mass- find using periodic table Particles= moles x 6.023 x 10 23

13. Examples Moles to mass 1. 2.0 mol of CaO 2. 0.6 mol of BeSe 3. 1.35 mol of Li3P 4. 0.35 mol of Be2SO4

14. examples Find moles given mass 1. 18.02 g of H2O 2. 80.92 g of HBr 3. 5.0 g of CaCl2 4. 0.26g of Ca3(PO4)2 5. 15.0 g of MgCl2 6. 86.7g of H3PO4 1 mol, 1mol, 0.045 mol, 0.00084 mol,0.16 mol, 0.885 mol

15. Assignments Assignment: molar mass/ moles/mass assignment

16. examples Moles to particles: 1. 1 mol of Fe 2. 3 mols CO 3. 0.671 mols H2O 4. 0.1001 HBr 6.023 x 10 23, 18.069 x1024, 4.04x 1023, 6.023x 1022

17. Examples Particles to moles 1. 6.023 x 10 23 atoms of Fe 2. 1.20 x 10 23 atoms of O2 3. 2.4 x 10 24 atoms of H 4. 1.8 x 10 24 atoms of K 1.0 mol, 0.199 mol, 3.987 mol, 2.99 mol

18. Examples Mass from particles 1. mass of 1.20 x 10 24 molecules of water? 2. mass of 2.41 x 10 24 atoms of barium hydroxide? 3. mass of 1.51 x 10 22 atoms of neon? 4. mass of 7.53 x 10 22 molecules of CH 4 ?

19. Particles from mass 1. How many molecules does 36.0 grams of water represent? 2. How many molecules does 11.0 grams of CO 2 represent? 3. How many atoms does 3.0 grams of carbon represent? 4. How many formula units does 200.0 grams of calcium carbonate represent?

20. assignment Stoichiometery problems with # of molecules Stoichiometery assignment with all the examples