IPS Unit 12 Stoichiometry Section 2 The Mole

Unit 12 – Section 2: The Mole

The Mole What is a dozen? Can you have a dozen cookies? Unit 12 – Section 2: The Mole The Mole What is a dozen? Can you have a dozen cookies? Can you have a dozen pencils? If you have a dozen cars, how many do you have? What is a dozen?

Mole is abbreviated mol Unit 12 – Section 2: The Mole The Mole What is a Mole? A counting number/unit (like a dozen) 1 mol = 6.02x1023 items 6.02 X 1023 (in scientific notation)) 602 billion trillion 602,000,000,000,000,000,000,000 Mole is abbreviated mol

The Mole How big is a mole? Unit 12 – Section 2: The Mole 1 mole of hockey pucks would equal the mass of the moon! 1 mole of basketballs would fill a bag the size of the earth! 1 mole of pennies would cover the Earth 1/4 mile deep! 1 mole of soft drink cans would cover the surface of the earth to a depth of over 200 miles. 1 mole unpopped popcorn kernels spread across the United States of America would cover the country to a depth of over 9 miles.

The Mole Dozens vs. Moles 1 dozen cookies = 12 cookies Unit 12 – Section 2: The Mole The Mole Dozens vs. Moles 1 dozen cookies = 12 cookies 1 mole of cookies = 6.02 X 1023 cookies 1 dozen cars = 12 cars 1 mole of cars = 6.02 X 1023 cars 1 dozen Al atoms = 12 Al atoms 1 mole of Al atoms = 6.02 X 1023 atoms Note that the NUMBER is always the same, but the MASS is very different!

Chocolate Chip Cookies!!! Unit 12 – Section 2: The Mole Chocolate Chip Cookies!!! 1 cup butter 2 eggs 1/2 cup white sugar 2 ½ cups flour 1 cup packed brown sugar 1 teaspoon baking soda 1 teaspoon vanilla extract 1 teaspoon salt 2 cups semisweet chocolate chips Makes 3 dozen How many eggs are needed to make 3 dozen cookies? How much butter is needed for the amount of chocolate chips used? How many eggs would we need to make 9 dozen cookies? How much brown sugar would I need if I had 1 ½ cups white sugar? Mole Ratio = moles of one substance to moles of another substance

Chocolate Chip Cookies!!! Unit 12 – Section 2: The Mole Chocolate Chip Cookies!!! 1 cup butter + ½ cup sugar + 1 cup brown sugar + 1 teaspoon vanilla + 2 eggs + 2 ½ cups four + 1 teaspoon baking soda + 1 teaspoon salt + 2 cups chocolate chips (177ºC) COOKIES (a synthesis reaction)

Unit 12 – Section 2: The Mole Cookies and Chemistry?!?!? Just like chocolate chip cookies have recipes, chemists have recipes as well Instead of calling them recipes, we call them chemical equations Furthermore, instead of using cups and teaspoons, we use grams and moles Lastly, instead of eggs, butter, sugar, etc. we use chemical compounds as ingredients

Formula Mass the mass in grams of one mole of a substance Unit 12 – Section 2: The Mole Formula Mass the mass in grams of one mole of a substance the formula mass and the atomic mass of an element are related: 1 atom Na = 23.0 amu Na 1 mole Na = 23.0 g Na Formula mass is used to convert between mass of a substance and number of moles

Molar Mass Conversions Unit 12 – Section 2: The Mole Molar Mass Conversions Using the Formula Mass for a compound, and knowing that there is one mole for the Formula Mass, we can preform conversion calculations between moles and grams

Molar Mass Conversions Unit 12 – Section 2: The Mole Molar Mass Conversions Conversion Guidelines Start with what you are given. Let the units guide you. The units will tell you if grams or moles goes on top. Multiply the top; multiply the bottom; top divided by the bottom

Molar Mass Conversions Unit 12 – Section 2: The Mole Molar Mass Conversions EX1: If you have 25g of NaCl, how many moles of NaCl do you have? 25g NaCl 1 mol NaCl 25 58.5 = 58.5 g NaCl = 0.43 mol NaCl NaCl Na 1 x 23.0 = 23.0 Cl 1 x 35.5 = 35.5 58.5 g NaCl

Molar Mass Conversions Unit 12 – Section 2: The Mole Molar Mass Conversions EX1: If you have 3.2 mols of NaCl, how many grams do you have? 3.2mol NaCl 58.5 g NaCl 187.2 1 = 1 mol NaCl = 187.2 g NaCl NaCl Na 1 x 23.0 = 23.0 Cl 1 x 35.5 = 35.5 58.5 g NaCl