Mole Notes packet 12 13 - Mr. Smith - Chem resourcessmithchem.weebly.com/.../1704463/mole_notes_packet_2016.doc · Web viewCalculate the percent composition of Al2(SO4)3? Hydrates

Mole Notes packet 12 13

Name ______________________________________________ Date _________________ Per ______

Remember: H-7

H

2

N

2

O

2

F

2

Cl

2

Br

2

I

2

Pre-AP Chemistry

=

=

CHEMICAL QUANTITIES

& THE MOLE

=

Name:

__ _____ Period:

2015

Chemistry Calendar

Monday

Tuesday

Wednesday

Thursday

Friday

January 19

20

21

Remember:

H

-

7

H

2

N

2

O

2

F

2

Cl

2

Br

2

I

2

22

23

End 2nd Semester

Half day

February 2

Notes:

Molar Mass &

Mole Map Conversion

Factors

(Hwk: pg. 7)

3

Particles to Moles

(calculations)

(Hwk: pg. 9)

4

Volume Mole Conversions:

Mixed Calculations

(Hwk: pg. 11)

5

Multi-step Conversions

(g > mol > L)

(Hwk: pg. 13)

6

Conversions QUIZ

% Composition Problems

(Hwk: pg. 15-16)

10

Empirical Formulas

(Hwk: pg. 18)

11

Empirical & Molecular Formulas

(Hwk: pg 19-20)

12

Test Review Due

(p. 20-21)

% Comp of a Penny Lab

13

14

Unit 6-Mole TEST

28

29

30

Unit 6: MOLE MATH Notes

Warm-up:

Give the units for the following measurements:

Length:

o Temperature:

Mass:

o Density:

Volume:

*NOTES

We use a unit called the _____________________, or _______________, to measure the amount of a substance. The mole can represent _________________(__________), _____________________(___________), or ________________________(__________).

*You must ALWAYS go through the MOLE!*

1 mole = _______________________________

1 mole = _______________________________

1 mole = _______________________________

Avogadros Number =

and is also called a

1 dozen = _______________ items.

3 dozen cookies = ______________ cookies

.5 dozen doughnuts = _________ doughnuts

A dozen is a counting unit equal to _________ of any object.

A Mole is a counting unit equal to

of any object, even really small ones like

,

, or

.

What is so special about 6.02 X 1023? Why do scientists use that number?

Example Conversion Factors:

1 mole = 6.02 x 1023 particles (atoms, molecules, or formula units)

1 mole of copper = 6.02 x 1023

of copper

1 mole of CuCl2 =

formula units of CuCl2

1 mole of CO2 =

molecules of CO2

The amount of substance containing Avogadros number of any kind of chemical unit is called a

of that substance.

One mole of K contains

atoms.

One mole of NaOH contains

formula units.

1

Molar Mass #1

For any monatomic element,

mole of that element is equal to its

.

For example, complete the following equalities.

mol Si =

g Si

g Ca = mol Ca

Diatomic Elements

The following elements do not naturally occur as one atom- they are always in a pair:

1.

*Trick to remembering the seven diatomics*

Molar Mass:

Molar mass is the mass of ______________________________ of a substance.

Other names for molar mass include:

One

of any element will have a mass in grams corresponding to the value of its

. For example:

1 mol Carbon = 12.01 g/mol

1 mol Nitrogen = 14.01 g/mol

1 mole of oxygen has a mass of 15.999 grams (its atomic mass from the periodic table).

2

One

of any molecule/compound will have a mass in grams corresponding to the value of its molar mass (the sum of the masses of the elements that compose it).

Ex. H2O

H: 1.01 X 2 = 2.02

O: 16.00 X 1 = 16.00

------------------

18.02 g/mole

Ex. Ca(NO3)2

Ca: 40.08 x 1 = 40.08

N: 14.01 x 2 = 28.02

O: 16.00 x 6 = 96.00

---------------------

164.10 g/mole

Sample Problems #1-2: Calculate the molar mass for the following compounds:

1. Carbonic acid ( _________________ (carbonate = CO32-)

# of H atoms:x

=

+

# of C atoms:

x

=

+

# of O atoms:x

=

________________

2. Ammonium sulfate ( ____________________ (sulfate = SO42-)

# of N atoms:x

=

+

# of H atoms:x

=

+

# of S atoms:

x

=

+

# of O atoms:x

=

________________

PRACTICE: (SHOW ALL WORK & UNITS to receive full credit.)

No Naked numbers (g/mole)

1. What is the atomic mass of sodium?

2. Calculate the molar mass for Al2(SO4)3.

3. Calculate the molar mass for nitrogen (hint: is he diatomic!?!?!).

4. H2SO4

5. ethanol (C2H5OH)

6. Potassium Chloride

7. Copper II Sulfate

3

Mole Highway

4

PRACTICE: Moles & Mass

Draw the Mole Road Map:

Molar mass:

called gram atomic mass when single element is used.

called gram formula unit when ionic compound is used.

called gram molecular unit when molecular compound or diatomic molecules used.

Diatomic molecules are atoms that bond with themselves. There are SEVEN of these that you need to remember: Br2 I2 N2 Cl2 H2 O2 F2 (Remember this by the name Brinclhof)

5

Conversion Factors:

1 mole = 6.02 x 1023 particles (Avogadros number)

1 mole = molar mass (Sum of atomic masses in grams)

1 mole = 22.4L of any gas at STP (Standard temperature & pressure)

Any gas density at STP = molar mass / molar volume

PRACTICE: (SHOW ALL WORK & UNITS to receive full credit.)

Determine the number of moles in each of the quantities below.

1. 25 g Sodium Chloride

1.1.

2. 125 g H2SO4

2.

Determine the number of grams in each of the quantities below.

3. 2.5 moles of Sodium Chloride

3.3.

4. 0.50 moles of H2SO4

4.

Solve the following mole-mass conversion problems.

5. How many moles are there in 27 g of ethanol (C2H5OH)?

5.

6

Homework: Moles & Mass

Conversion Factors:



1 mole = 22.4L of any gas at STP (Standard temperature & pressure)


Convert to moles (SHOW ALL WORK & UNITS to receive full credit.)

1. 100 g KMnO4

1.

2. 74 g Potassium Chloride

2.

2.

3. 35 g Copper II Sulfate

3.3.

Convert to grams (SHOW ALL WORK & UNITS to receive full credit.)

4. 1.7 moles of KMnO4

4.

5. 0.25 moles of Potassium Chloride

5.

5.

6. 3.2 moles of Copper II Sulfate

6.

Solve the following (SHOW ALL WORK & UNITS to receive full credit.)

7. How many moles of NaCl are in 16.0 grams of NaCl?

7.

8. How many grams of glucose, C6H12O6, are there in 4.67 moles of glucose?

8.

7

NOTES : REPRESENTATIVE PARTICLES (( MOLES

Warm-up:

List the diatomic elements:

Representative Particles

A representative particle is the __________________________________________________.

Types of Particles (atoms / molecules / formula units)

Atoms = ___________________

Molecules= _____________________

Formula Units = ________________________

Monatomic elements = ____________________

Diatomic elements = _____________________

Ionic Compounds = ________________________

Molecular (Covalent) Compounds = _______________________

Ions = ______________________

Acids = _____________________

Avogadros number, which is

, represents the number of chemical units in one mole of any substance. For the monatomic elements, the chemical unit is an

. 1 mol of any chemical =

particles.

Examples (1 mol = 6.02 x 1023 atoms / molecules / formula units)

1 mol CaCl2 =

1 mol Ca2+ =

1 mol HCl (aq) =

1 mol P2O5 =

1 mol Ca =

1 mol Cl2 =

Particles ( Moles OR Moles ( Particles

Sample Problems

1. How many moles are in 4.50x1025 atoms of manganese?

2. How many atoms are found in 3.27mol of magnesium?

3. Chalk is composed primarily of calcium carbonate. How many particles are in 3.4 moles of calcium carbonate?

8

Particles ( Moles OR Moles ( Particles Homework

Now You Try! Remember to show all work and report your answers with the correct number of significant figures and the correct units!

1. How many moles are found in 9.26x1026molecules of CO2?

2. How many atoms are found in 12mol of barium?

3. How many formula units are found in 3.55 mol of NaCl?

4. How many moles are in 4.27 x 1045 molecules carbon tetrachloride?

5. How many moles are present in 2.45 x 1023 molecules of CF4?

6. Iodine is an element required by humans in order to produce thyroid hormones. To help prevent iodine deficiencies in the US, our table salt is enriched with iodine. If you need 0.0219 g per year, how many moles of iodine are required per year? (Remember iodine is a diatomic!) How many particles would that be?

Ha Ha

9

NOTES: VOLUME (( MOLES

WARM-UP:

1. How many atoms are in 0.75 mol zinc?

NOTES:

In Chemistry, we use the initials,

, to represent standard temperature and standard pressure.

standard temperature =

standard pressure =

The molar volume of any gas at STP is

L. In other words, one mole of any gas

at STP is equal to

.

Conversion Factors:



1 mole =

______L of any _______ at STP (Standard temperature & pressure)


Moles ( Liters and Liters ( Moles

Sample Problems

(SHOW ALL WORK & UNITS to receive full credit.)

1. The average lung capacity of a male is 6.0L. The average lung capacity of a female is 4.7L. Assume the following:

If your TEACHERs lungs are completely filled with oxygen, determine the number of moles of oxygen gas in the lungs of your chemistry teacher at STP.

2. At STP, how many moles are found in 54L of neon gas?

3. How many liters are found in 3.02mol of helium at STP?

Homework: Mixed Mole Problems

Now You Try! Remember to show all work and report your answers with the correct number of significant figures and the correct units! USE YOUR MOLE MAP!!

1. How many grams are in 14.05mol silver?

2. How many moles are in 895g of Ba(OH)2?

3. How many moles are in 50.0g of argon?

4. At STP, neon is a gas. How many moles are found in 0.317L?

5. How many liters are in 44.3moles of helium gas at STP?

Mixed Mole

Solve the following problems. SHOW ALL WORK! Report your answer with the correct units and the correct number of significant figures.

1. Assuming STP, how many moles are in 5.42 x 10-1 L Ne?

2. Convert 1.3 mol of neon into particles.

3. Determine the number of grams in 3.0mol of calcium nitride.

4. How many moles are in 45 grams carbon tetrachloride?

5. How many moles of magnesium is 3.01 x 1022 atoms of magnesium?

6. How many atoms are in 0.750 moles of zinc?

11

MULTI-STEP CONVERSIONS

Remember how to use your Mole Road Map! (You must always go through the ____________!)

I

Moles!

Sample Problems:

1. How many grams are in 45L of neon gas at STP?

2. How many formula units are in 36.4g of NaCl?

3. What is the mass of 550L of helium gas at STP?

4. How many liters are in 56g of helium gas at STP?

12

MULTI-STEP CONVERSIONS Homework

Now You Try! Remember to show all work and report your answers with the correct number of significant figures and the correct units!

1. How many liters are in 56g of helium gas at STP?

2. A 12 oz can of Coke contains 0.0345 g of caffeine, C8H10N4O2. Determine the number of molecules of caffeine in one can of Coke.

3. Laughing gas is dinitrogen monoxide. How many grams of dinitrogen monoxide gas are in 45.0L of laughing gas at STP?

4. Bromine comes from the Greek word meaning stench. It has a strong, irritating odor. How many atoms of bromine are found in 92.1g of bromine?

5. How many atoms are in 65.6 L of Fe?

6. What is the volume of 5.6g of sulfuric acid?

7. If you burned 6.10x1024 molecules of ethane (C2H6), what mass of ethane did you burn?

8. How many formula units are in 5.1g of titanium (IV) oxide?

9. A container contains 893L of neon gas. What is the mass of the gas in this container at STP?

13

PERCENT COMPOSITION

Warm-up:

Using the picture to the right, find the percent of the pie that belongs to Jamie.

*All %s must add up to 100.

Notes:

The percent composition of a substance or mixture is the _________________________ of each _____________________ or component.

To find % of an element in a compound, use

as the whole amount.

Example:

Percent Composition of Water (H2O):

____________ oxygen

____________ hydrogen

When asked to find the ____________ _________________, you are calculating the percentage of just _________ element in the substance or mixture.

PRACTICE:

1) Find % sodium in Na2O.

Molar mass = Na 22.99 x 2 = 45.98

% Na =

O 16.00 x 1 = 16.00 +

61.98 g

2) Find the % composition of a compound that has 5.34g C, 0.42g H, & 47.08g Cl.

Mass (total)= 5.34g + 0.42g + 47.08g = 52.84g

%C = 5.34g C x 100% =

C

52.84g

%H = 0.42g H x 100% =

H

52.84g

%Cl = 47.08g Cl x 100% =

Cl

52.84g

3) How many grams of sodium are in 650.0 g of Na2CO3?

Na:

X

=

(part sodium)

C:

X

=

(part carbon)

O:

X

=

(part oxygen)

TOTAL:

(Whole)

FORMULA:

part x grams(total) = Answer

grams Na =

whole

PERCENT COMPOSITION #2

1. Calculate the percent composition of C3H7OH (2-propanol).

2. Find the percent composition of a compound that has 2.62g Na and 4.04g Cl.

3. A certain form of penicillin, Penicillin F, has been analyzed. It contains 84.05 g of carbon, 10.08 g of nitrogen, 16.03 g of sulfur, and 32.00 g oxygen. Determine the mass percent of carbon present in the sample of Penicillin F.

4. Isopentyl acetate is released when a bee stings and is responsible for the scent of bananas.

a. If the formula for isopentyl acetate is C7H14O2, determine its percent composition.

b. Have you ever noticed a banana scented bee sting?

5. Which of the following compounds has the greatest mass percent of oxygen?

Nickel (III) carbonate

Lithium phosphate

6. Milk of magnesia, a common antacid, is a solution of magnesium hydroxide. If a sample of antacid contains 2.1 g of magnesium hydroxide, how much oxygen does the sample contain?

15

Homework: Percent Composition

1. KMnO4

Molar Mass Calculation

Percent Composition Calculation

% Composition Answer

K =

K =

K =

Mn =

Mn =

Mn =

O =

O =

O =

TOTAL=

TOTAL= 100%

2. HCl




H =

H =

H =

Cl =

Cl =

Cl =

TOTAL=

TOTAL= 100%

3. Mg(NO3)2




Mg =

Mg =

Mg =

N =

N =

N =

O =

O =

O =

TOTAL=

TOTAL= 100%

4. (NH4)3PO4




N =

N =

N =

H =

H =

H =

P =

P =

P =

O =

O =

O =

TOTAL=

TOTAL= 100%

5. How many grams of oxygen can be produced from the decomposition of 100.0g of KClO3? (In other words, what portion of a 100.0g sample of KClO3 is O?)

6. How much iron can be recovered from 25.0g Iron (III) Oxide?

7. How much silver can be produced from 125g Ag2S?

16

NOTES: Empirical Formulas

WARM-UP:

1. Calculate the percent composition of Al2(SO4)3?

Hydrates

A hydrate is a solid compound that contains a definite percentage of bound ___________________.

Cobalt (II) chloride hexahydrate

CoCl2 ___H2O

______________________________________

Sample Problem #1:

Calcium chloride dehydrate, CaCl2 2H2O, is used to control ice and dust on roads. Determine the mass percent of water present in this hydrate.

Sample Problem #2:

Manganese (II) chloride typically is found as a hydrate, MnCl2XH2O. If the mass percent of water is 36.41 %, determine X..

NOTES:

Empirical formula:

e.g., CH2O or CH

be reduced. May or may not exist in this form in the real world.

Molecular formula:

e.g., C2H4O2 or C6H6

be reduced. Formula describes a substance as it actually exists.

Empirical or Molecular? (Remember that for some compounds, its empirical formula can also be its molecular formula.)

Na2O

C3H6

K2SO4

C6H12O6

Which pair has the same empirical formula?

Na2O and Na2O2

C6H12O6 and CH2O

C3H6 and C5H12

C6H6 and C5H5

Calculating an Empirical Formula

1. Determine the _______________ of each ____________________.

2. Convert the mass of each to ____________________. (

3. Find the ___________ to _____________ ____________________ of each element by dividing the number of moles of each element by the ____________________________ number of moles.

4. If the ratio is not a ______________ number, multiply each ratio by a factor to _____________________________________.

5. Write the formula using the mole ratio as the _______________________________ for the formula.

Find empirical formula of 69.5% O & 30.5% N.

Step 1: Divide % or grams by its atomic mass to get moles of each element.

69.5g O 1 mole O = 4.34 mole O

30.5g N 1 mole N = 2.18 mole N

16.00g O

14.01g N

Step 2: Divide smallest mole number in each element to get ratio of that element.

4.34 mole O=

2.18 mole N =

* This answer becomes the subscript for that element; round to nearest whole number if .8 or higher.

ANSWER = NO2

What is the molecular formula for above if the molecular mass is 92g?

Step 3: For molecular formulas, find empirical formulas as above. Then find empiricals mass. Divide molecular mass (given in problem) by empiricals mass to get multiple of compound.

NO2 mass = 14.01 + (16.00 x 2) = 46.01g

92g/46.01g = 2

(NO2) x 2

Final Answer = N2O4

INDEPENDENT PRACTICE:

1. Analysis of a compound shows that it contains 10.88g of calcium and 19.07g of chlorine. Determine the empirical formula of this compound.

2. One of the most commonly used white pigments in paint is a compound of titanium and oxygen that contains 5.99 g titanium by mass and 4.01 g oxygen by mass. Determine the empirical formula and name for this compound.

3. Used in the production of nylon, adipic acid is an organic compound composed of 49.31% C, 43.79% O, and the rest is hydrogen. Determine the empirical formula of adipic acid.

4. Manganese (II) chloride typically is found as a hydrate.

MnCl2 XH2O

If the mass percent of water is 36.41%, determine X.

Calculating Molecular Formulas

The molecular formula will have the _________________ _________________ as the empirical formula.

To determine a molecular formula, we will _______________________ the ___________________ ____________________ by a whole number factor (WNF).

WNF=

1. Empirical Formula = P2O5

Molar Mass= 283.88 g/mol

What is the molecular formula of this compound?

2. Nitrogen and oxygen form multiple molecular compounds together. One of these compounds is used to fuel space shuttles and has the empirical formula NO2. If the molar mass of this compound is 92.02 g/ mol, what is the molecular formula?

3. Butane is commonly used in lighters. It is composed of 17.37% carbon and 82.63% hydrogen. It has a molar mass of 58.17 g/mol. What is the molecular formula of butane?

4. Vitamin C is 40.91% C, 4.587% H, and the remaining is oxygen. If the molar mass of Vitamin C is about 180 g/mol, determine the empirical and molecular formula.

Homework: Empirical and Molecular Formulas

What is the empirical formula (lowest whole number ratio) of the compounds below?

1)74.9% carbon, 25.1% hydrogen

2) 32.4% sodium, 22.5% sulfur, 45.1% oxygen

3)25.9% nitrogen, 74.1% oxygen

What is the molecular formula (whole number multiple ratio) of the compounds below?

4)A compound is 64.9% carbon, 13.5% hydrogen and 21.6% oxygen. Its molecular mass is 74 g/mol. What is its molecular formula?

5) A compound is 54.5% carbon, 9.1% hydrogen, and 36.4% oxygen. Its molecular mass is 88 g/mol. What is its molecular formula?

7. The empirical formula of a compound is NO2. Its molecular mass is 92 g/mol. What is its molecular formula?

8. The compound methyl butanoate smells like apples. Its percent composition is 58% C, 9.8% H, and 31.4% O. If its gram molecular mass is 102 g/mol, what is its molecular formula?

Pre-AP Chemistry Test Review

Chemical Quantities & The Mole TEST on

Problems: For the following problems, show all work and report your answers with the correct units and significant figures.

1. What is the molar mass of BaCO3?

2. In one molecule of P2O5, how many phosphorous atoms are present?____________

3. List all seven diatomics:

Name

Formula

12. Calculate the percent composition of Ca(OH)2.

13. Calculate the percent composition of diboron hexahydride.

14. How many atoms of C are in 3.6 moles of C?

15. Determine the number of moles of hydrogen that are in 362.8g of this element.

16. A chemical reaction produces 13.8 mol of carbon monoxide gas. What volume will the gas occupy at STP?

17. What is the mass of 5.0 X 1025formula units of Fe(NO2)3?

18. How many liters are there in 5.25g CO2 at STP?

19. How many grams of Ne are there in 5.5 moles of the gas?

20. Nomenclature Review

Name the following compounds

a. N2O

b. H2S

c. FeO

d. (NH4)2CO3

e. H2SO4

f. Ni(OH)2

Write the formulas for the following compounds.

a. dinitrogen tetroxide

b. copper(I) sulfide

c. calcium nitrate

d. sulfurous acid

e. gold(II) phosphate

f. pentaphosphorus decoxide

21. The term STP means: ___________________________________ which means:

22. Define empirical formula.

23. Define molecular formula.

24. Find the empirical formula for the following substances (a. and b.) using the information given:

a. A compound is composed of 38.67% potassium, 13.85% nitrogen, 47.48% oxygen. What is the empirical formula?

b. A compound is made up of 44.33% phosphorus and 57.18% oxygen- what is the empirical formula?

25. Determine the molecular formula for each of these compounds.

a. empirical formula = CH2O; the molar mass = 90 g/mol

b. empirical formula = HgCl; molar mass = 472.2 g/mol

26. The action of bacteria on meat and fish produces a poisonous compound called cadaverine. As its name and origin imply, it stinks! It is 58.77% C, 13.81% H, and the remainder is Nitrogen. Its molar mass is 102.2 g/mol. Find its empirical and molecular formula. (Hint: Find the empirical formula first.)

27. Determine the mass percent of water in K3P 3H2O.

EMBED PowerPoint.Slide.12

Mole

22.4 L

Volume

(gases only)

Molar Mass

(from periodic table)

in grams

6.02 X 1023

Representative Particles

(atoms, ions, molecules, formula units)

NOTES:

To convert between units, follow the highway. Notice, there is no shortcut from grams to liters or between any of the three units surrounding the mole.

This means you have to convert to before converting to another unit!

=

=

1 MOLE

Q: Why was the mole of oxygen molecules so excited after he left the party?

A:

MASS PROBLEMS

VOLUME PROBLEMS

Particles

atoms

formula units molecules

Liters at STP

Mass (grams)

Mole

Jamies

slice

Remember: H-7

H2

N2

O2

F2

Cl2

Br2

I2

Documents

Mole Notes packet 12 13 - Mr. Smith - Chem resourcessmithchem.weebly.com/.../1704463/mole_notes_packet_2016.doc · Web viewCalculate the percent composition of Al2(SO4)3? Hydrates