The Mole Chap. 11 No, not that mole!

I.Counting Particles

A.There are common units to count things

I.Counting Particles A.There are common units to count things 1.Pair

I.Counting Particles A.There are common units to count things 1.Pair = 2 2.Dozen

I.Counting Particles A.There are common units to count things 1.Pair = 2 2.Dozen = 12 3.Ream

I.Counting Particles A.There are common units to count things 1.Pair = 2 2.Dozen = 12 3.Ream = 500 sheets 4.Gross

I.Counting Particles A.There are common units to count things 1.Pair = 2 2.Dozen = 12 3.Ream = Gross = ‘Scop’ (not really)

I.Counting Particles A.There are common units to count things 1.Pair = 2 2.Dozen = 12 3.Ream = Gross = ‘Scop’ (not really) = 64 6.Mole

I.Counting Particles A.There are common units to count things 1.Pair = 2 2.Dozen = 12 3.Ream = Gross = ‘Scop’ (not really) = 64 6.Mole = Avogadro’s #

Avogadro’s number A value equal to x We’ll round it to: 6.02 x 10 23

I.Counting Particles B.Converting with moles 1.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?

I.Counting Particles B.Converting with moles 1.Finding the number of particles from moles. 2.Finding the number of moles from particles.

Self Check – Ex. 3 A sample of lead contains 1.5 x atoms. How many moles of lead atoms are there?

Self Check – Ex. 4 A sample of zinc chloride contains x formula units. How many moles of zinc chloride are there?

II. Massing a Mole A.Different atoms have different masses.

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

3 dozen atoms

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

II. Massing a Mole A.Different atoms have different masses. B.The mass on the P.T. represents...

II. Massing a Mole A.Different atoms have different masses. B.The mass on the P.T. represents... 1.The mass of 1 atom (in amu)

II. Massing a Mole A.Different atoms have different masses. B.The mass on the P.T. represents... 1.The mass of 1 atom (in amu) 2.The mass of 1 mole of atoms (in grams)

II. Massing a Mole A.Different atoms have different masses. B.The mass on the P.T. represents... C.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.

6.02 x 10 23

II. Massing a Mole D.Calculating with molar mass 1.Using molar mass you can convert from to.

II. Massing a Mole D.Calculating with molar mass 1.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?

II. Massing a Mole D.Calculating with molar mass 1.Using molar mass you can convert from grams to moles. 2.You can also convert from _____ to.

II. Massing a Mole D.Calculating with molar mass 1.Using molar mass you can convert from grams to moles. 2.You can also convert from moles to grams.

Self Check – Ex. 6 What is the mass of 0.25 moles of chromium?

II. Massing a Mole D.Calculating with molar mass E.Calculating the molar mass of compound

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

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

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

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

One mole of CH 4 contains: Example 1 mole of carbon 4 moles of hydrogen weighs 12 g weighs 4 x (1) g = 16 g/mol

II. Massing a Mole D.Calculating with molar mass E.Calculating the molar mass of compound 1.Add the masses of each of the atoms in the compound.

II. Massing a Mole D.Calculating with molar mass E.Calculating the molar mass of compound 1.Add the masses of each of the atoms in the compound. 2.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, LiNO 3 ?

Self Check – Ex. 8 What is the molar mass of calcium acetate, Ca(C 2 H 3 O 2 ) 2 ?

III. Molar Volume of Gas The volume of 1 mole of gas particles when measured at STP

III. Molar Volume of Gas A.This is determined at specific conditions. STP – standard temperature (0ºC) and standard pressure (1 atm)

III. Molar Volume of Gas A.This is determined at specific conditions. B.It’s the same for all gases. 1 mole of gas at STP = 22.4 L

III. Molar Volume of Gas A.This is determined at specific conditions. B.It’s the same for all gases. C.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.

IV. Multiple step conversions Just remember the mole is the central unit

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

Self Check – Ex. 11 What is the mass of 11.2 L of carbon dioxide gas?

Self Check – Ex. 12 How many molecules of ammonia, NH 3 are in a 68-g sample?

IV.Mole ratios in chemical formulas

A.The subscripts can give a ratio of atoms in a compound.

1 mole of N 1 mole of ammonia, NH 3 mole of N mole of N

1 mole of N 1 mole of ammonia, NH 3 3 mole of N

1 mole of N 1 mole of ammonia, NH 3 1 mole NH 3 : 1 mole N 3 mole of N 1 mole NH 3 : 3 mole H

1 mole of N 1 mole of ammonia, NH 3 1 mole NH 3 : 1 mole N 3 mole of N 1 mole NH 3 : 3 mole H 1 mole NH 3 1 mole N 1 mole NH 3 1 mole N

IV.Mole ratios in chemical formulas A.The subscripts can give a ratio of atoms in a compound. B.Conversions

Self Check – Ex. 13 How many moles of hydroxide ions are in 1.2 moles of magnesium hydroxide, Mg(OH) 2 ?

Self Check – Ex. 14 What is the mass of the oxygen atoms in 4 moles of sodium sulfate?

The end.