How many is that?

How many is that? 1 Couple of 2 kittens

How many is that? 1 dozen 12 meatballs

How many is that? 1 gross of 144 pencils

How many is that? 1 mole of 602,200,000,000,000,000,000,000 stars

1 mole = 602,200,000,000,000,000,000,000

The Mole ?

The Mole ! 602,200,000,000,000,000,000,000 6.022 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 6.022 x 1023

Avogadro’s Number 6.022 x 1023 = “Avogadro’s Number”. I didn’t discover it. It’s just named after me! AmadeoAvogadro(1776-1855)

What’s the mass of … • 1 dozen kittens? (1 kitten weighs 3 lbs) 1 dozen 3 lbs 12 kittens 36 lbs 1 dozen 1 kitten

What’s the mass of … • 6 dozen meatballs? (1 meatball weighs 35 grams) 6 dozen 35 grams 12 meatballs 2520 grams 1 dozen 1 meatball

What’s the mass of … • 3 gross pencils? (1 pencil weighs 15 grams) 3 gross 15 grams 144 pencils 6480 grams 1 gross 1 pencil

What’s the mass of a mole??? Depends... If it’s a mole of kittens, we take the mass of one kitten… and multiply by how many kittens. 3 lbs x 6.022 x 1023 If it’s a mole of Carbon atoms, it’s easier than that! Carbon’s atomic mass = 12.0 grams/mole

SUPER IMPORTANT CONCEPT! Molar Mass = the mass (in grams) of 1 mole (6.022 x 1023) of anything • Finding the molar mass of an element is pretty easy! • Take it’s atomic mass and make the units • “X grams/1 mole of Xatoms” Try it: Molar mass of Lithium? Helium? Iron? 6.94 grams/1 mole Li atoms 4.00 grams/1 mole He atoms 55.85 grams/1 mole Fe atoms

Calculations with Moles:Converting moles to grams How many grams of lithium are in 3.50 moles of lithium? 3.50 mol Li 6.94 g Li = g Li 24.29 1 mol Li

Calculations with Moles:Converting grams to moles How many moles of lithium are in 18.2 grams of lithium? 18.2 g Li 1 mol Li = mol Li 2.62 6.94 g Li

Calculations with Moles:Using Avogadro’s Number How many atoms of lithium are in 3.50 moles of lithium? 6.02 x 1023atoms 3.50 mol = atoms 2.11 x 1024 1 mol

Calculations with Moles:Using Avogadro’s Number How many atoms of lithium are in 18.2 g of lithium? 18.2 g Li 6.022 x 1023 atoms Li 1 mol Li 6.94 g Li 1 mol Li (18.2)(6.022 x 1023)/6.94 1.58 x 1024 = atoms Li

You try it! If you had 107.92 grams of Aluminum foil, how many moles of Aluminum are there? = moles Al atoms

You try it! If you had 3.011 x 1023 atoms of Calcium, how many grams of Calcium are there? = grams Ca

What about for compounds, you ask??? Since a compound is more than one atom bonded, just add the masses of all the atoms there Example: Carbon Dioxide (CO2) 12.01 g + 2(16.00 g) = 44.01 g One mole of CO2 (6.02 x 1023 molecules) has a mass of 44.01 grams

You try it! 1 mole of NaCl would weigh exactly how many grams? = grams NaCl 6 moles of NaCl would weigh exactly how many grams? = grams NaCl

You try it! How many grams of Dihydrogen Monoxide are in 6.022 x 1023 molecules of Dihydrogen Monoxide? = grams H2O

Standard Molar Volume Equal volumes of all gases at the same temperature and pressure contain the same number of molecules. -Amedeo Avogadro At STP (Standard Temperature and Pressure): Standard Temperature = 0˚ C Standard Pressure = 1 atmosphere 1 mole of a gas occupies 22.4 liters of volume

Calculations with Moles:Using Standard Molar Volume How many molesof hydrogen are in 100 L of hydrogen at STP? 1 mol 100 L = mol 4.46 22.4 L

Calculations with Moles:Using Standard Molar Volume How many liters are occupied by 3 moles of oxygen gas at STP? 22.4 L 3 mol = L 67.2 1 mol

You try it! 16 moles of Cl2 gas would occupy how many liters? = L Cl2 16 moles of Cl2 gas would have a mass of how many grams? = grams Cl2

Do it all at once! 35 grams of carbon tetrafluoride gas would occupy how many liters? 35 g 1 mol CF4 22.4 L = L CF4 8.9 88.01 g 1 mol

You try it! 1373 grams of N2 gas would occupy how many liters? …………………………………………………..= L N2

Atoms or molecules Liters Mole Relationships 22.4 L 22. 4 L 6.02 x 1023 Mole Atomic Mass Grams

How many is that?

How many is that?

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