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 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

3 1 atom of carbon would weigh ____ times more than 1 atom of helium. dozen atoms 1 atom of carbon would weigh ____ times more than 1 atom of helium. 3 dozen atoms

3 1 atom of carbon would weigh ____ times more than 1 atom of helium. 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

One mole of CH4 contains: Example One mole of CH4 contains: 1 mole of carbon moles of hydrogen

One mole of CH4 contains: Example One mole of CH4 contains: 1 mole of carbon 4 moles of hydrogen

One mole of CH4 contains: Example One mole of CH4 contains: 1 mole of carbon 4 moles of hydrogen weighs 12 g weighs ______

One mole of CH4 contains: Example One mole of CH4 contains: 1 mole of carbon 4 moles of hydrogen weighs 12 g weighs 4 x (1) g

One mole of CH4 contains: 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?

Multiple step conversions Just remember the mole is the central unit

(atoms, molecules, formula units) Mass (grams) Volume (liters) MOLE particles (atoms, molecules, formula units)

Self Check – Ex. 12 How many molecules of ammonia, NH3 are in a 68-g sample?

The end.