How many eggs are there in 5 dozen?

How many moles are in 2.25 grams of the element iron, Fe?

Standard: Utilize appropriate mathematical equations and processes to solve chemistry problems. 3221.Math.1

Objective: The learner will convert the amount of a substance by using molar conversions through dimensional analysis.

Introduction to the Mole

What is a mole?Mole – SI base unit used to measure the amount of a substance

What is molar mass?Molar mass – the mass in grams of one mole of a substance (ex. hydrogen 1.0079g/mol)

What is the conversion factor for molar mass?

1 mole= mass of an atom (mass number)

Practice

What is the number of moles found in 50.4 grams of Uranium?

Calculate the number of moles of 80.850 g of nitrogen.

Calculate the number of moles in 334 grams of lead.

Moles to Grams6.0 moles carbon= __________ grams carbon 4.5 x 103 moles K = ___________ grams K

Determine the mass in grams of 19.73 moles of the element boron, B.

8.90 mol Ca = ___________ g Ca

2.8 mol Fe = ___________ g Fe

4.59 x 102 mol F = _____________ g F

6.000 mol S = ____________ g S

PROVE IT!!!!!!!

5.68 g N= ___ mol N

0.405 mol N

0.0821 mol Rb= ___ g Rb

7.02 g Rb

3400 g O= ___ mol O

210 mol O

34.71 mol As= ___ g As

2600. g As

Exit slipDetermine the number of moles of 46.3 grams of the element, copper, Cu?Evaluate and explain in words how you solve this problem. Tell me step by step in complete sentences (4 to 5 sentences).

HomeworkWhat is the mass in grams of .375 mol of the element

potassium, K.

What is the mass in grams of 0.0135 mol of the element, sodium, Na?

How many moles of gold, Au, are in 3.6 x 10-10 g

How many moles of copper, Cu, are in 3.22g of copper?

Standard: Utilize appropriate mathematical equations and processes to solve chemistry problems. 3221.Math.1

Objective: The learner will convert the amount of a substance by using Avogadro’s number through dimensional analysis.

Avogadro’s Number and Molar Conversions

Avogadro’s NumberAvogadro was born in Italy from 1776-1865

His field of study was physics.

He developed Avogadro’s number which is 6.022 x 10 23

6.022 x 1023 = 1 mol

Moles to Avogadro’s Number 0.30 mol of F = ______ atoms F.

2.66 mol of N= ______ atoms N?

How many atoms are in 4.2 mol O?

Avogadro’s Number to Moles 6.7 x 1026 atoms of Zn= _______ moles Zn

1.69 x 1023 atoms of V= _______ moles V?

How many moles are in 3.29 x 1021 atoms Al?

Practice Please !!!!!!

0.187 mol Ca = _________ atoms Ca

How many atoms are in 1.45 x 10-17 moles of As? 5.00 x 1021 atoms of S = __________ moles S

How many moles of neon are in 7.60 x 1024 atoms?

PROVE IT!!!!!!!

5.68gN=__mol N

0.0821 mol Rb=__g Rb

0.187molCa=__atoms Ca

7.60 x 1024Ne atoms=___ moles Ne

Exit Slip

How many moles are in 4.5 x 1024 atoms of Ni?

How many atoms are 78.94 moles of iodine?

HOMEWORK!!!!!

Page 86 Practice Problems 1-3.Write the questions and show your work.

Standard: Utilize appropriate mathematical equations and processes to solve chemistry problems. 3221.Math.1

Objective: The learner will convert two step molar conversions. The learner will calculate the molecular weight of a compound, and apply it to molar conversions.

Entrance SlipFind the mass in grams of

3.012 x 1024 atoms of Ca. The molar mass is 40.08 g/mol

Converting Grams to atoms

Example:1. Calculate the number of atoms in a 356 g

sample of Ti?2. Determine the number of atoms in 7.60 g

of He.3. 841 g Mn = __________ atoms of Mn

Converting Atoms to Grams

Example:1. Find the mass in grams of 2.44 x 1024

atoms of carbon, whose molar mass is 12.01 g/mol.

2. Find the mass in grams of 2.11 x 1024 atoms of copper, whose molar mass is 63.55g/mol.

3. 5.46 x 1024 atoms Pb = __________g Pb

Mole Relay RaceStudent #1- Read the problem and set the problem up for the correct number

of steps.Student #2- Place the units in the set

up.Student #3- Fill in the correct

conversion factors.Student #4- Solve and write the answer

with the correct number of sig. figs.

Exit Slip

4.06 x 1024 atoms Cu = _______ g Cu

702 grams P = ________ atoms P

Molar Conversion 2- Step Homework

1. Determine the number of moles of fluorine in 9.23 x 10-9 g of fluorine.

2. How many atoms of germanium are in 3.00 x 106 g Ge?

3. What is the mass in grams of 1.2 x 1025 atoms of the element bromine, Br?

4. How many atoms of beryllium are in 1.67 x 103 g of Be?

5. What is the mass in grams of 9.70 x 1023 atoms of magnesium, Mg?

Molecular Weight

What is the molecular weight of HCl?

Molecular weightMolecular weight – the mass in grams of one moles

of a substance. (g/mol)

What is the molecular weight of the following:NaClH2O

Ca(NO3)2

Mg(NO3)2

How many moles are in 67.68 grams of Al2S3?

345.0 grams of NaOH= ________ mol of NaOH 5.6 moles of HBr= _______ grams of HBr

200.5 grams of MgCl2 = _______ mol of MgCl2

4.5 moles SiCl4 = _____ molecules SiCl4

2.3 moles of CaS = _______ formula units CaS

Determine the number of moles of F2 in 5.6 x 1023 molecules of F2.

Exit Slip

How many grams are in 8.9 moles of Li2O?

How many molecules are in 5.90 moles of CO?

267 grams of LiBr = ______ formula units LiBr

7.8 x 1024 molecules of CO2 = _____ grams of CO2

149.0 grams of OF2 = ______ molecules OF2

HOMEWORK

Determine the mass in grams of 89.0 moles of NaNO3?

6.00 grams of B2(SO4)3= ____ formula units of B2(SO4)3

7.8 x 1024 formula units of Ba3P2 = ____ moles of Ba3P2

5.6 x 1025 formula units V3(PO4)5= _____ grams V3(PO4)5

Standard: Convert among the following quantities of a substance:

mass, number of moles, and number of particles.

Objective: The learner will review

molar conversions.

Fine the molecular weight of potassium chlorate.

What is the mass in grams of 2.50 moles of oxygen, O2?

Ibuprofen, C13H18O2, is the active ingredient in many nonprescription pain relievers. Its molar

mass is 206.31 g/mol.a. If the tablets in a bottle contain a total of 33

grams of ibuprofen, how many moles of ibuprofen are in the bottle?

b. How many molecules are in the bottle?c. What is the total mass of carbon in 33 grams

of ibuprofen?

How many moles are there in 6.60 grams of (NH4)2SO4?

How many grams of nitrogen is in 6.60 grams of ammonium sulfate?

How many grams of oxygen are in 6.60 grams of ammonium sulfate?

Practice Problems

How many grams of Al are in 43.8 g of Al2S3?How many grams of chlorine are there in 0.35 moles of CH2Cl2?

What is the mass of chlorine in 3.36 grams of MgCl2?What is the mass of phosphorus in 135.0 grams of K3PO4?How many grams of nitrogen are in 2.01 moles of N2O5?

Let’s RACE

Mole Relay Race1. Read the problem and set the

problem up for the correct number of steps.

3. Place the units in the set up.4. Fill in the correct conversion factors.5. Solve and write the answer with the

correct number of sig. figs.

Exit Slip

How many grams of phosphorus are in 1.02 moles of Ca3(PO4)2?

Homework

How many grams of hydrogen are there in 4.5 g of Ca(OH)2?

How many grams of carbon are there in 3.4 grams of C12H22O11?

How many grams of nitrogen are in 0.35 moles of Cu(NO3)2?

Standard: Analyze ionic and covalent compounds in terms of

percent composition.

Objective: The learner will evaluate the percentage composition of

atoms in chemical formulas.

In what subjects would you most likely use percentages?

Percentage Composition

Percentage CompositionWhat is percentage composition?

the percent by mass of each element in a compound

Percentage Composition

What is the equation for percentage composition?

(Number of atoms of an element)(molar mass) X 100 = % of element Molecular weight of the compound in compound

Percentage Composition Example 1: Find the percentage composition of copper sulfide, Cu2S.

Step 1: Write the equation.

Step 2: Choose one element to solve.

Step 3: Count the number of atoms that the element has. Substitute that number into the equation.

Step 4: Find the molar mass of the element. Substitute that number into the equation.

Step 5: Calculate the molecular weight of the compound. Substitute that number into the equation.

Step 6: Solve

Step 7: Check your work by adding the percentages. Your final answer should be at least 100%

ProblemCalculate the percentage composition of the (NH4)2CO3.

Calculate the percentage composition of sodium nitrate, NaNO3.

Calculate the percentage composition of calcium hydroxide, Ca(OH)2

Rally Coach

Group 1: Calculate the percentage composition of Ag2SO4.

Group 2: Calculate the percentage composition of Cu(NO3)2.

Group 3: Calculate the percentage composition of NaCl.

Group 4: Calculate the percentage composition of FeSO3.

Group 5: Calculate the percentage composition of CaCO3.

Group 6: Calculate the percentage composition of H2S.

Group 7: Calculate the percentage composition of MgF2.

Student A: Calculate the percentage composition of Ag2SO4.

Student B: Calculate the percentage composition of Cu(NO3)2.

Exit Slip

Calculate the percentage composition of Al2S3.

ClassworkWrite the statement. FIVE POINTS will be deducted is the

statements are not written. TEN POINTS will be deducted if work is not shown.

Calculate the percentage composition of SrBr2.

Calculate the percentage composition of CaSO4.

Calculate the percentage composition of Mg(CN)2.

Calculate the percentage composition of Pb(NO3)2.

Calculate the percentage composition of Fe(MnO4)3.

Standard: Convert percentage composition into an empirical

formula.

Objective: The learner will investigate empirical formulas.

Empirical Formula

Formulas and Percentage Composition

Empirical formulas- a chemical formula that shows the composition of a compound. (ratios of atom)

Determine Empirical Formulas from Percentage Composition

1. Percent to mass (grams)-Assume that you have 100g of the substance.

2. Mass (grams) to mole

3. Divide by the least number of moles.

4. Multiply 'til whole

Determine Empirical Formulas from Percentage Composition.

Example1. Chemical analysis of a liquid shows that it

is 60.0% C, 13.4 %H, and 26.6% O by mass. Calculate the empirical formula of this substance.

2. A dead alkaline battery is found to contain a compound of Mn and O. Its analysis gives 69.6% Mn and 30.4% O.

Determine Empirical Formulas from Percentage Composition.

1. A compound is 38.77% Cl and 61.23% O.

2. A liquid compound is 18.0 % C, 2.26% H, and 79.7% Cl.

Determine Empirical Formulas from Percentage CompositionExit Slip.

1. A compound contains 5.88% hydrogen and 94.12% oxygen. What is the empirical formula?

Determine Empirical Formulas from Percentage Composition Homework.

1. A compound is made up of 92.3% carbon and 7.7% hydrogen. What is the empirical

formula?

2. A compound contains 70.0% iron and 30.0% oxygen. What is the empirical

formula?

Standard: Convert empirical formulas to molecular formulas.

Objective: The learner will investigate molecular formulas.

Molecular Formula

Determine Molecular Formulas from Empirical Formula.

Molecular formula- a chemical formula that shows the number and kinds of atoms in a molecule.

Steps1. Write the information that is given.2. Find the molar mass of the empirical formula.3. Solve using this formula. n= experimental molar mass of compound

molar mass of empirical formula4. Multiply the empirical formula by n to get the molecular formula.

Determine Molecular Formulas from Empirical Formula.

Example:

•The empirical formula for a compound is P2O5. Its experimental molar mass is 284 g/mol. Determine the molecular formula of the compound.

• Determine the molecular formula of a compound with an empirical formula of NH2 and a molar mass of 32.06 g/mol.

Determine Molecular Formulas from Empirical Formula.

Example:

•A sample with a formula mass of 34.00 g/mol is found to consist of 0.44g H and 6.92g O. Find its molecular formula.

•A compound with formula mass of 42.08 g/mol is found to be 85.64% carbon and 14.36% hydrogen by mass. Find its molecular formula.

Determine Molecular Formulas from Empirical Formula.

•A compound has an experimental molar mass of 78 g/mol. Its empirical formula is CH. What is its molecular formula?

•A compound has the empirical formula CH2O. Its experimental molar mass is 90.0 g/mol. What is its molecular formula?

• If 4.04g of N combine with 11.46g O to produce a compound with a formula mass of 108.0 g/mol, what is the molecular formula of this compound?

Determine Molecular Formulas from Empirical Formula.

Exit Slip

Determine the molecular formula of a compound with an empirical formula of C2H4S and a formula mass of 179 g/mol.