1. THE MOLE... a unit of counting Quantities in Chemical Reactions

2. Big Ideas Relationships in chemical reactions can be described quantitatively The efficiency of chemical reactions can be determined and optimized by applying an understanding of quantitative relationships in such reactions.

3. Today How do chemists calculate and express the number of atoms or molecules in a substance? How many atoms are in a 27g piece of aluminium foil? Take a guess

4. How Scientists Keep Track of Atoms One way to measure how much of a substance is available is to count the # of particles in that sample However, atoms & molecules are extremely small To solve this problem, scientists developed the concept of the mole SYMBOL IS n. *The mole is a unit songThe mole is a unit

5. The Mole A dozen donuts = 12 A mole of donuts = 6.023x10 23 a dozen shoes = 12 A mole of shoes = 6.023x10 23 1 mole = 6.02 x 10 23 entities of a substance 1 mole of anything = 6.023x10 23 = 602,000,000,000,000,000,000,000!!!

6. WHAT IS THE MOLE? Avogadro’s Constant = N A = 6.023 x 10 23 particles 1 mol Units of moles are mol Different types of particles include: atoms OR molecules OR ions OR electrons OR formula units, etc. FYI…. A formula unit is a term used to represent the lowest whole number ratio of ions in an ionic compound. On your calculator: EE or EXP or x10^

7. WHERE DID THIS NUMBER COME FROM? A mole is the amount of substance that contains as many particles as exactly 12.000g of Carbon-12

8. The Mole- Examples 1 mole of carbon contains 6.02 x 10 23 atoms of carbon 1 mole of H 2 O contains 6.02 x 10 23 molecules of H 2 O 1 mole of NaCl contains 6.02 x 10 23 formula units of NaCl

9. How Big is Avogadro’s Number? ◦ 6.02 x 10 23 ÷ 1,000,000 = 6.02 x 10 17 d o 6.02 x 10 17 d ÷ 365 d/a = 1.65 x 10 15 a If you had one mole of dollars, how long would it take to spend it at a rate of $1,000,000 per day? Put this into perspective… o The sun is about 4.6 x 10 9 years old and will burn out in about 5 x 10 9 years. o You will need to spend faster!!

10. Just How Big is a Mole? Enough soft drink cans to cover the surface of the earth to a depth of over 200 miles. If you had Avogadro's number of unpopped popcorn kernels, and spread them across the United States of America, the country would be covered in popcorn to a depth of over 9 miles. If we were able to count atoms at the rate of 10 million per second, it would take about 2 billion years to count the atoms in one mole.

11. The mole is a BIG number. The green pea analogy puts it into perspective as well: Did you know that 12 pencils will contain a mole of carbon atoms?

14. Learning Check Suppose we invented a new collection unit called a trapp. One trapp contains 8 objects. 1. How many paper clips in 1 trapp? a) 1b) 4c) 8 2. How many oranges in 2.0 trapp? a) 4b) 8c) 16 3. How many trapps contain 40 gummy bears? a) 5b) 10c) 20

15. How many times would 1 mole of green peas fill the Atlantic ocean? 1. Volume of 1 mol of peas -need to look it up or measure with water displacement/math  V pea = 0.2mL V mol pea = 0.2mL x 6.023. 10 23 don’t forget to convert units. In this case mL to L 2. Google V ocean = ….. 3. Divide…L/….L

16. Variables to Know n = number of moles N = number of particles N A = Avogadro’s number (6.02 × 10 23 ) Two possible types of questions: o Moles to Particles  N = n x N A o Particles to Moles  n = N / N A N NANA n

17. Using Avogadro’s Constant How many atoms in 2 moles of carbon? N = n x N A = 2 moles x (6.02 x 10 23 ) = 1.2 x 10 24 particles of C How many moles is 5.0 x 10 24 particles of iron? n= N / N A = 5.0 x 10 24 /6.02 x 10 23 = 8.3 moles of Fe How many atoms in 2 moles of water? N= n x N A = 2 moles x 6.02 x 10 23 = 1.2 x 10 24 molecules of H 2 O = 3 atoms per molecule = 3 x (1.2 x 10 24 ) = 3.6 x 10 24 atoms in 2 moles of H 2 O

18. LEARNING CHECK (round to 3 sig. figs.)  How many molecules of CO 2 are in 4.56 moles of CO 2 ?  How many moles of water is 5.87 x 10 22 molecules?  How many moles is 7.78 x 10 24 formula units of MgCl 2  How many atoms of carbon are in 1.23 mol of C 6 H 12 O 6 ?  Try another…  How many electrons are in 1.5 mol of CO 2 ? 2.75 x 10 24 molecules 0.0975 mol (or 9.75 x 10 -2 ) 4.44 x 10 24 atoms C 12.9 moles

19. Size of a Mole Assignment To better understand the immensity of the mole you will compare a mole of something to a mole of something else that can be pictured…. BE CREATIVE!! Eg. Mass of one mole of a substance How much honey would one mole of bees produce in one season compared to the mass of water in the Atlantic Ocean? Time to complete one mole of a task How long would it take in years to blink 6.023 x 10 23 times? Volume of a substance If you had a mole of green peas covering the earth, how deep would the layer be?

20. There are 3 parts to this assignment: 1. Pick a unique question that compares 1 mole of something to another thing that can be seen visually. 2. Perform the correct calculations 3. Make a picture to show the size comparison 4. 1 min presentation

21. Rubric Level 4Level 3Level 2Level 1 Unique Question that compares 2 things that can be pictured [A-10] Question is unique The entities compared are easily pictured Calculations are correct and show the size comparison [I-10] Calculations use GRASP & have units [I-10] All calculations are correct All units included All work logically shown (GRASP) Picture is creative and shows the size comparison well [C-10] Presented well Neat and attractive picture Size comparison is clear.

22. Mass to Mole Calculations Atomic Mass ◦Mass of one atom ◦Unit μ = atomic mass unit = a.m.u  Eg. Each hydrogen atom has a mass of 1.001μ ◦1 μ equals approximately 1.67 x 10 -24 g, which is extremely small and not practical to measure. Enter Molar Mass….

23. Molar Mass (MM) The mass of 1 mole of a substance Mass of 6.023 x 10 23 particles Units are g/mol ◦Eg. The molar mass of Hydrogen is 1.01 g/mol

24. Molar Mass Molar mass and atomic mass have the same numbers except there is a unit difference. The g/mol unit is more useful that μ because… It can be measured in the lab using a scale Atomic MassMolar Mass Li6.94 μ/atom6.94 g/mol Ag107.86 μ/atom107.86 g/mol

25. Eg. Find the molar mass of water: H 2 O H: 2 x 1.001g/mol O: 1 x 16.00 g/mol 18.002g/mol Eg. Find the molar mass of calcium phosphate: Ca 3 (PO 4 ) 2 Ca: 3 x 40.08 g/mol P:2 x 30.97 g/mol O: 8 x 16.00 g/mol 310.2g/mol

26.  The same as:  Gram Molecular Mass (for molecules)  Gram Formula Mass (ionic compounds)  Gram Atomic Mass (for elements)  molar mass is just a much broader term than these other specific masses

27. Complete the following chart **because this is a chart and not a table you can include units and calculations in the boxes. Substanc e Type of Particle (atom, molecule, formula unit etc.) Mass of 6.023 x 10 23 particles (Molar Mass) Atomic Mass (μ) Ne O3O3 C 6 H 12 O 6 KClO 3 Pb NH 3 LiBr

28. 1 Mole in a Beaker Activity Calculate the mass of one mole of each substance. Show your calculations in the boxes below. Measure out one mole of each substance into a 400mL beaker and draw a line on the beaker in the table to show how much space one mole of that substance takes up. 1 mole of Cu1 mole of Pb 1 mole of NaCl 1 mole of C 12 H 22 O 11 1 mole of H 2 O1 mole of C

29. Mole Calculations MM m n MM = m/n n = m/MM m = MMn Factor Label! Let the units guide you N = nN A n = N/N A

30. Converting between Mass and Mole

31. HOMEWORK pp. 232 #1, 4, 5, 7, 8, 11, 15 Quiz tomorrow – one question from homework. A mole is a unit