1. Warmup: 5 minutes 1. Why do we use moles? Makes it easier to measure chemical quantities because atoms and molecules are very small. 2. Define the following ‘molecabulary’ words demoleition molearchy molectomy 3. a. What is a mole's favorite movie? b. What did Avogadro teach his students in math class? c. What kind of fruit did Avogadro eat in the summer?

2. Mole Conversions *need calculator and PT demoleition - the destruction which moles bring about in your yard. molearchy - government in which moles are in complete control; under this government Mole Day is celebrated twice a year and chemistry is the only scientific subject taught in school molectomy - the process of removing a mole's insides

3. a. What is a mole's favorite movie? b. What did Avogadro teach his students in math class? c. What kind of fruit did Avogadro eat in the summer? The Green Mole Moletiplication Watermolens

4. Mole Day Song “Let It Be” = “Twenty-Three” When I find myself in times of trouble Avogodro's number comes to me Six point oh two two, e twenty three. The mole is a counting number And you'll find few who disagree Six point oh two two, e twenty three. Twenty three, twenty three Twenty three, ya twenty three. A mole is six point oh e twenty three The molar mass of an atom is on The periodic table you will read The number of atoms is six point oh e twenty three To convert from grams to atoms It's the molar mass that you will need Times by six point oh two e twenty three Twenty three twenty three Twenty three, ya twenty three A mole is six point oh e twenty three

5. Ex 1: What is the molar mass of CH 4 ? C: 1 mole x 12.01 = 12.01 H: 4 mole x 1.01 = 4.04 = 16.05 g/mole Calculating Molar Mass 1) Find the atomic mass of each element 2) Multiply the number of moles times the atomic mass of for each element 3) Add values, round to the hundredths place, and report your answer in g/mole

6. Ex 2: What is the molar mass of Na 2 SO 4 ? Na: 2 mole x 22.99 = 45.98 S: 1 mole x 32.07 = 32.07 O: 4 mole x 16.00 = 64.00 = 142.05 g/mole Calculating Molar Mass 1) Find the atomic mass of each element 2) Multiply the number of moles times the atomic mass of for each element 3) Add values, round to the hundredths place, and report your answer in g/mole

7. Ex 3: What is the molar mass of Pb(NO 3 ) 2 ? Pb: 1 mole x 207.20 = 207.20 N: 2 mole x 14.01 = 28.02 O: 6 mole x 16.00 = 96.00 = 331.22 g/mole Ex 4: Find the mass % of each element in Pb(NO 3 ) 2 Pb 207.20 g/mole 331.22 g/mole = 0.6256 or 62.56% N 28.02 g/mole 331.22 g/mole = 0.0846 or 8.46% O 96.00 g/mole 331.22 g/mole = 0.2898 or 28.98%

8. Ex 5: Find the mass percent of the element indicated. Calculate molar mass first! 1. Hydrogen Peroxide element: hydrogen 2. Oxygen Gas element: oxygen 3. Cesium Carbonate element: cesium 4. Sodium Hydroxide element: sodium H 2 O 2 34.02 g/mol 2.02/34.02 = 5.94% O 2 32.00 g/mol 100.00% Cs 2 CO 3 325.83 g/mol 265.82/ 325.83 = 81.58% NaOH40.00 g/mol 22.99/40.00 = 57.48%

9. Conversions using Molar Mass Ex 6: How many moles is 5.69 grams of CH 4 ? 5.69 g CH 4 ( ) = ( ) Remember, we already calculated the molar mass of methane in g/mole in Ex 1!!!!!!! 1 mole CH 4 16.05 g CH 4 0.355 mole CH 4

10. Ex 7: How many moles is 4.56 g of CO 2 ? 4.56 g CO 2 ( ) = ( ) You need the molar mass of carbon dioxide 1 mole CO 2 44.01 g CO 2 0.104 mole CO 2

11. Ex 8: Find the mass (in grams) of 9.8 moles of lithium fluoride 9.8 mole LiF ( ) = ( ) You need the formula and molar mass of this compound FIRST! 25.94g LiF 1 mole LiF 250 g LiF

12. Moles of Chalk!