1. Chapter 10.1 Stoichiometry

2. Stoichiometry Stoicheion: relationship Metron: amount How # particles, mass and volume of matter are related

3. Measuring Matter You can measure matter in three ways 1.Number of particles( #atoms, #molecules) 2.Mass (mg, g, kg) 3.Volume (ml, L) Different measurements can be converted into each other using conversion factors

4. Particles in Chemistry Representative Particles (RP) in chemistry 1.atoms 2.compounds 3.ions Abbreviated: # RP

5. RPs in chemistry are so small They are grouped into larger packages called moles

6. The mole (lower cased) 1 mole has 6.02 x 10 23 RPs called Avogadro’s Number

7. RP’s in chemistry are written in scientific notation 6.02 x 10 23 Coefficient Exponent

8. Meaning of a decadic exponent 10 0 = 1 10 1 = 10 10 10 2 = 100 10 x 10 10 3 = 100010 x 10 x 10 10 -1 = 0.11/10 1 10 -2 = 0.011/10 2 10 -3 = 0.001 1/10 3

9. 3 Rules for correct scientific notations #1. Coefficient has to be a number larger/equal than 1.00 and smaller than 10 #2. Has to have two decimals (round or add zeros) #3. Do all math with the coefficient, then adjust exponent

10. Correct the following Scientific Notations 1.0.09 x 10 9 RP 2.2,315.74 x 10 23 RP 3.100.74 x 10 -6 RP 4.0.34 x 10 -10 RP Write the following numbers in scientific notation 5. 103 6. 0.23 7. 2,894.78

11. 1. Converting between Particles and Moles Converting moles to particles ___1 mole___ or __6.02 x 10 23 RP 6.02 x 10 23 RP 1 mole

12. Steps to solve Stoichiometry Problems 1. Pathway PW 2. Substitute with conversion factors 3. Reduce and solve 4. Write an answer sentence

13. Practice Q1: How many molecules (RP) are in 19.76 moles? PW: Moles → RP 19.76 moles X 6.02 x 10 23 RP = 1 1 mole Q 2:

14. How many moles are 8.25 x 10 25 ions?

15. Explain to a neighbor a)the advantages of writing numbers in scientific notation b)The rules of scientific notation

16. 2. Molar Mass Mass of elements are listed in the periodic table is called Average Atomic Mass - AAM What is the AAM of Carbon? We called it 12.01 amu New: 12.01 g new unit!!! 1 mole Means: 1 mole of Carbon has the mass of 12.01 gram This is the socalled Molar Mass

17. Practice What is the Molar Mass of O, K, S-33, 14 6 C O: 16.00 g 1 mole K: 39.10 g 1 mole S-33 33.00 g 1 mole 14 6 C: 14.00 g 1 mole

18. 2. Molar Mass of Molecules: Example CO 2 add the mass of the individual elements together 1 x C = 12.01 g/ mol 2 x O = 2 x 16.00g = 32.00 g/ mol Total 44.01 g/mole Means one mole of CO 2 has the mass of 44.01 g Conversion factor: 1 mole CO2 or 44.01 g 44.01 g 1 mole CO2

19. Practice What is the molar mass of 1.C 2 H 4 2.Mg(OH) 2 3.Water 1. 28.06g/mole 2. 58.33 g/mole 3. 18.02 g/mole

20. Warm-up Calculate the molar masses of 1.C 3 H 8 2.Aluminum carbonate 3.Dinitrogen tetrahydride Answer: 1.44.11 g/mole 2.Al 2 (CO 3 ) 3 233.99 g/mole 3.N 2 H 4 32.06 g/mole

21. Stoichiometry with Mass/Moles/#RP Pathway connections Mass #RP does not exist! Instead: Go over mole island! Mass ↔ Mole ↔ #RP 1.What is the mass of 2.4 moles of CO 2 ? MM=44.01 g/mole

22. Practice Mass ↔ Mole ↔ #RP What is the mass of 1.87 x 10 24 molecules of CO 2 ?

23. How many moles are in 20.00 g of water?

24. # Atoms in One Molecule

25. How many atoms are in …molecules Total up all atoms in a molecule: Example: C 6 H 12 O 6 6 Carbon atoms, 12 Hydrogen, 6 Oxygen 6+12+6 =24 atoms in one molecule C 6 H 12 O 6

26. Conversion factor for atoms in C 6 H 12 O 6 1 molecule C 6 H 12 O 6 or ___24 atoms_____ 24 atoms 1 molecule C 6 H 12 O 6

27. Practice Q 1: How many atoms are in 3.6 x 10 23 molecules of C 6 H 12 O 6 ? Q2: How many atoms are in 4.5 moles of NH 3 ?