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The Mole. Chap. 11. No, not that mole!. Counting Particles. Counting Particles. There are common units to count things. Counting Particles. There are common units to count things. Pair. Counting Particles. There are common units to count things. Pair = 2 Dozen . Counting Particles.
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The Mole Chap. 11 No, not that mole!
Counting Particles • There are common units to count things
Counting Particles • There are common units to count things • Pair
Counting Particles • There are common units to count things • Pair = 2 • Dozen
Counting Particles • There are common units to count things • Pair = 2 • Dozen = 12 • Ream
Counting Particles • There are common units to count things • Pair = 2 • Dozen = 12 • Ream = 500 sheets • Gross
Counting Particles • There are common units to count things • Pair = 2 • Dozen = 12 • Ream = 500 • Gross = 144 • ‘Scop’ (not really)
Counting Particles • There are common units to count things • Pair = 2 • Dozen = 12 • Ream = 500 • Gross = 144 • ‘Scop’ (not really) = 64 • Mole
Counting Particles • There are common units to count things • Pair = 2 • Dozen = 12 • Ream = 500 • Gross = 144 • ‘Scop’ (not really) = 64 • Mole = Avogadro’s #
Avogadro’s number A value equal to 6.0221367 x 1023. We’ll round it to: 6.02 x 1023
Counting Particles • Converting with moles • Finding the number of particles from moles.
Self Check – Ex. 1 How many atoms are in 2 moles of helium?
Self Check – Ex. 2 How many molecules are in 7.5 moles of carbon dioxide?
Counting Particles • Converting with moles • Finding the number of particles from moles. • Finding the number of moles from particles.
Self Check – Ex. 3 A sample of lead contains 1.5 x 1024 atoms. How many moles of lead atoms are there?
Self Check – Ex. 4 A sample of zinc chloride contains 2.150 x 1018 formula units. How many moles of zinc chloride are there?
Massing a Mole • Different atoms have different masses.
1 atom of carbon would weigh ____ times more than 1 atom of helium. 3
dozen atoms 1 atom of carbon would weigh ____ times more than 1 atom of helium. 3 dozen atoms
mole of 1 atom of carbon would weigh ____ times more than 1 atom of helium. 3 mole of
Massing a Mole • Different atoms have different masses. • The mass on the P.T. represents. . .
Massing a Mole • Different atoms have different masses. • The mass on the P.T. represents. . . • The mass of 1 atom (in amu)
Massing a Mole • Different atoms have different masses. • The mass on the P.T. represents. . . • The mass of 1 atom (in amu) • The mass of 1 mole of atoms (in grams)
Massing a Mole • Different atoms have different masses. • The mass on the P.T. represents. . . • This value is called the molar mass. The mass of 1 mole of particles
If you weigh out 40 grams of argon you have essentially counted ______________ atoms.
If you weigh out 40 grams of argon you have essentially counted ______________ atoms. 6.02 x 1023
Massing a Mole • Calculating with molar mass • Using molar mass you can convert from to .
Massing a Mole • Calculating with molar mass • Using molar mass you can convert from grams to moles.
Self Check – Ex. 5 If a sample of aluminum has a mass 81.0 g how many moles are present?
Massing a Mole • Calculating with molar mass • Using molar mass you can convert from grams to moles. • You can also convert from _____ to .
Massing a Mole • Calculating with molar mass • Using molar mass you can convert from grams to moles. • You can also convert from moles to grams.
Self Check – Ex. 6 What is the mass of 0.25 moles of chromium?
Massing a Mole • Calculating with molar mass • Calculating the molar mass of compound
Example One mole of CH4 contains: 1 mole of carbon moles of hydrogen
Example One mole of CH4 contains: 1 mole of carbon 4 moles of hydrogen
Example One mole of CH4 contains: 1 mole of carbon 4 moles of hydrogen weighs 12 g weighs ______
Example One mole of CH4 contains: 1 mole of carbon 4 moles of hydrogen weighs 12 g weighs 4 x (1) g
Example One mole of CH4 contains: 1 mole of carbon 4 moles of hydrogen weighs 12 g weighs 4 x (1) g = 16 g/mol
Massing a Mole • Calculating with molar mass • Calculating the molar mass of compound • Add the masses of each of the atoms in the compound.
Massing a Mole • Calculating with molar mass • Calculating the molar mass of compound • Add the masses of each of the atoms in the compound. • Remember to multiply each atom’s mass by the number atoms in the compound.
Self Check – Ex. 7 What is the molar mass of lithium nitrate, LiNO3?
Self Check – Ex. 8 What is the molar mass of calcium acetate, Ca(C2H3O2)2?
Molar Volume of Gas The volume of 1 mole of gas particles when measured at STP
Molar Volume of Gas • This is determined at specific conditions. STP – standard temperature (0ºC) and standard pressure (1 atm)
Molar Volume of Gas • This is determined at specific conditions. • It’s the same for all gases. 1 mole of gas at STP = 22.4 L
Molar Volume of Gas • This is determined at specific conditions. • It’s the same for all gases. • Conversions
Self Check – Ex. 9 What is the volume of 3 moles of carbon dioxide gas at STP?
Self Check – Ex. 10 How many moles of air are in a 64 L that is at 1 atm and 0ºC.
Multiple step conversions Just remember the mole is the central unit