Cobalt (III) carbonate C02(CO3)3 Iron (III) phosphide FeP

When naming an ionic

compound, which ion

always comes first?

DMA 2/3/11

How do you know if a compound is ionic or covalent? What are the differences in

naming the 2 types of compounds?

DMA 2/4/11

To Do TodayFinish your ionic naming

worksheet

Finish your Ch 9-1 questions #1-4 (assigned to you while the substitute was here)

Watch a video about Chemistry

What are chemical reactions and why do they

occur?

DMA 2/7/11

What are 4 signs of a chemical

reaction?

DMA 2/8/11

In the Lab Today Safety gear! You are REQUIRED to wear

goggles and aprons.

After your group has had their pre-labs stamped, you may get your materials.

Be sure that you take the mass of the baggie with all components inside before and after the reaction.

The baggie needs to stay sealed at all times!

Observe before, during, and after for part A and part B

Observe the baggie for at least 15 minutes.

What are the 4 parts of a

good lab conclusion?

DMA 2/9/11

Answer to DMA Claim-restate your hypothesis (what you

expected to happen)

Evidence-data and specific information from your experiment

Explain- how does your evidence support your hypothesis

Conclude- what was the most important thing you learned from this activity?

Today’s ItineraryWork on post-lab:

Gather “after” observations from nail

Write a conclusion

Answer the Essay question (should fill a page) You have until 10:40 to work If you aren’t done, finish it as homework

Then: AAR from me “After Action Report”

Hook & ? Equations

Did anything happen in the 2 activities we just did?

Did we end up with the same substances before and after?

So, did a chemical reaction take place? How do we know?

Which of the 5 signs of a chemical reaction did we see in these 2 activities? Color change Temperature change Formation of a gas Formation of a solid

Hook & ? Equations

The 2 reactants were: NaHCO3 and CaCl2

The catalyst is: phenol red The water in it speeds the reaction The color change indicated the products were

acidic

The products were: NaCl, CaCO3, H2O, CO2

Try writing a chemical equation for this in your notebooks.

Hook & ? Equations

The nail plus the copper(II) nitrate Is this ionic or covalent? Is it soluble?

What do you think is happening with the nail?

We start with a blue solution We have copper and nitrate ions

Added in a nail-the iron is what is reacting with the solution

What is the solid that was formed?

Write the formulas for the following compounds:

Beryllium nitratenickel (III) sulfitezinc phosphatemanganese(IV)

carbonate

DMA 2/10/11

Answer to DMA Beryllium nitrate:

Be(NO3)2

Nickel (III) sulfite Ni2(SO3)3

Zinc phosphate Zn3(PO4)2

Manganese carbonate Mn(CO3)2

Write the formulas for the following compounds:

copper (II) acetatesodium hydroxide

lithium oxidecobalt (III) carbonateiron (III) phosphide

DMA 2/11/11

Answer to DMA Copper (II)

acetate Cu(C2H3O2)2 Also written as

Cu(CH3COO)2

Sodium hydroxide NaOH

Lithium oxide Li2O

Cobalt (III) carbonate C02(CO3)3

Iron (III) phosphide FeP

No DMAA few

directions, then we will go to the library.

DMA 2/14/11

What are the 5 types of

reactions? (Look in your notes

from last week)

DMA 2/15/11

Classifying Types of Reactions

On your work sheet-

Write out the name of each compound in the equation

Example: 1. Magnesium +oxygen Magnesium

oxide

Then, list the type of reaction (the above is a synthesis reaction)

Due Tomorrow Classifying equations worksheet

Section 9-1 questions #1-4

Lab notebookHook & Question Equations (lab in a bag)

Including the conclusion and the essay questionHow to do Types of Reactions

Including the conclusion and observations of each reaction

Quiz tomorrow includes: Naming Balancing 5 types of reactions

Write the equation:1. Barium plus nitrogen yields barium nitride.

2. Oxygen plus iron yields iron (III) oxide.

3. Tin (IV) chloride plus ammonium sulfide yields tin (IV) sulfide plus ammonium chloride.

DMA 2/17/11

Write the equation:

1. Calcium acetate plus sodium

carbonate yields sodium acetate

plus calcium carbonate.

2. Potassium chlorate yields

potassium chloride plus oxygen.

DMA 2/18/11

Turn in: Classifying equations worksheet

Section 9-1 questions #1-4

Lab notebookHook & Question Equations (lab in a bag)

Including the conclusion and the essay questionHow to do Types of Reactions

Including the conclusion and observations of each reaction

The QuizChange the directions to:

For #1-11 balance the equation, for #12-16 classify the type of reaction

Chapter 9

Chemical Reactions

Indicators 1. Evolution of Heat or Light

- Exothermic – gives off heat- Endothermic – absorbs heat

2. Production of a gas

3. Formation of a precipitate

4. Change in color

Chemical reaction Atom arrangement - Atoms aren’t created

or destroyed. They are re-arranged

Expressed as:

sentence Copper reacts with chlorine to form copper

(II) chloride.

word equationCopper + chlorine ® copper (II) chloride

Diatomic elements

There are 9 elements that never want to be alone.

They form diatomic molecules.

H2 , N2 , O2 , F2 , Cl2 , Br2 , I2 , P4 and

S8

The –ogens and the –ines

1 + 7 pattern on the periodic table

Symbols used in equations

the arrow separates the reactants from the products

Read “reacts to form”

The plus sign = “and”

(s) after the formula -solid

(g) after the formula -gas

(l) after the formula -liquid


(aq) after the formula - dissolved in water, an aqueous solution.

used after a product indicates a gas (same as (g))

¯used after a product indicates a solid (same as (s))


indicates a reversible reaction (More later)

shows that heat is supplied to the reaction

is used to indicate a catalyst used supplied, in this case, platinum.

heat ,

Pt

Significance of an Equation

1. Indicates relative amounts of reactants and products – proportions

2. Allow for calculation of masses

3. Indicates whether the reaction can be reversed.

DMA – February 4, 2009

Write the equation:Barium plus nitrogen yields barium

nitride.Oxygen plus iron yields iron (III) oxide.Tin (IV) chloride plus ammonium sulfide

yields tin (IV) sulfide plus ammonium chloride.

Calcium acetate plus sodium carbonate yields sodium acetate plus calcium carbonate.

Potassium chlorate yields potassium chloride plus oxygen.

DMA – February 4, 2008

Solid iron (III) sulfide reacts with gaseous hydrogen chloride to form iron (II) chloride and hydrogen sulfide gas.

Nitric acid dissolved in water reacts with solid sodium carbonate to form liquid water and carbon dioxide gas and sodium nitrate dissolved in water.

February 4, 2009 Class

Writing Chemical Equation worksheet

Homework Finish worksheet

Skeleton Equation Uses formulas and symbols to describe a

reaction

doesn’t indicate how many.

All chemical equations are sentences that describe reactions.

February 5, 2009 Write the word equations and balance the

reactions

Fe(g) + O2(g) ® Fe2O3(s)

Cu(s) + AgNO3(aq) ®

Ag(s) + Cu(NO3)2(aq)

February 5, 2009 Class

Notes – Balancing Equations Synthesis and Decomposition

Homework Worksheets 2 and 3

Balancing Chemical Equations

Balanced Equation

Atoms can’t be created or destroyed

All the atoms we start with we must end up with

A balanced equation has the same number of each element on both sides of the equation.

C + O2 ® CO2

This equation is already balanced

What if it isn’t already?

C + OO® COO

C + O2 ® CO

We need one more oxygen in the products.

Can’t change the formula, because it describes what is

C + O® COO

Must be used to make another CO

But where did the other C come from?

C +O

®C

OO

OC

Must have started with two C

2 C + O2 ® 2 CO

C

+O

®C

OO

OC

C

Example

H2 + H2OO2®

Make a table to keep track of where you are at

Example

H2 + H2OO2®

Need twice as much O in the product

R PH

O

2

2

2

1

Example

H2 + H2OO2®

Changes the O

R PH

O

2

2

2

1

2

Example

H2 + H2OO2®

Also changes the H

R PH

O

2

2

2

1

2

2

Example

H2 + H2OO2®

Need twice as much H in the reactant

R PH

O

2

2

2

1

2

2

4

Example

H2 + H2OO2®

Recount

R PH

O

2

2

2

1

2

2

4

2

Example

H2 + H2OO2®

The equation is balanced, has the same number of each kind of atom on both sides

R PH

O

2

2

2

1

2

2

4

2

4

Example

H2 + H2OO2®

This is the answer

R PH

O

2

2

2

1

2

2

4

2

4

Not this

Examples

CH4 + O2 ® CO2 + H2O

AgNO3 + Cu ® Cu(NO3)2 + Ag

Mg + N2 ® Mg3N2

P + O2 ® P4O10

Na + H2O ® H2 + NaOH

Classify each reaction from

the 5 types in your notes

CH4 + 2O2 ® CO2 + 2H2O

2AgNO3 + Cu ® Cu(NO3)2 +

2Ag

3Mg + N2 ® Mg3N2

NaCl +AgNO3 ® NaNO3 +

AgCl

2NaCl ®2Na + Cl2DMA 2/23/11

#4

Define the following: precipitate

polyatomic iondiatomic element

DMA 2/25/11

For the Pre-Lab You need to read the ENTIRE lab, this is a

complicated one and it is important you know what you are doing!

Be sure to translate the names to formulas (step 3)

Flowcharts-should fill a WHOLE page, I want sketches to be: detailed easy to interpret well labeled

You may work on this with ONE partner, with one lab report for both of you—do it on a separate piece of paper, not in a lab notebook.

Correct the formulas you wrote on your lab-use a different color so you can see where your

mistake was and learn from it! DMA 2/28/11

DMA 3/1/11

DMA 3/2/11

Explain the difference

between ionic and covalent bonds. Give an example

compound of each.

DMA 3/3/11If you don’t know the answer to this—look it up!!

To Do Today Finish your labsstart

now, today is the LAST day to work on it.

Finish your post lab Copper cycle-the

chemical equations for all the reactions we did PLUS classify each type of reaction You already have all the

compounds on your lab sheet

Conclusion

Due Today: Balancing equations

worksheet

Homework Due Monday Chapter 10-1-

CORNELL notes and questions #1-4

Through “Mass-Mole relationships” in packet

NO WASTING TIME TODAY

Balance and Classify these chemical equations

1. C2H5OH + O2 CO2 + H2O ______

2. Al + CuCl2 AlCl3 + Cu ______

3. NaOH + Ni(NO3)2 NaNO3 + Ni(OH)2 ______

4. N2 + I2 NI3 ______

5. C6H12O6 + O2 CO2 + H2O ______

6. CO2 + H2O C6H12O6 + O2 ______

Balance and Classify these chemical equations

1. calcium + oxygen calcium oxide2. copper (II) nitrate + iron

iron (II) nitrate + copper3. Ammonium nitrate

dinitrogen dioxide + dihydrogen monoxide4. Chlorine + sodium bromide

sodium chloride + bromine5. Sodium phosphate + calcium chloride

sodium chloride + calcium phosphate6. Potassium chlorate

potassium chloride + oxygen

How many moles are in: 0.25 g of C6H12O6

24 g of Mg(OH)2

How many grams are in: 0.95 mol CO2

DMA 3/7/11

Cu-Again – Chemical EquationsReactants Products

Starting Substances End Products

Cu + HNO3 Cu(NO3)2 + NO2 + H2O

Cu(NO3)2 + NaOH Cu(OH)2 + NaNO3 + heat

Cu(OH)2 + heat CuO + H2O

CuO + HCl CuCl2 + H2O

CuCl2 + Al Cu + AlCl3

Al + HCl AlCl3 + H2

An equation Describes a reaction

Must be balanced because to follow Law of Conservation of Energy

Can only be balanced by changing the coefficients.

Has special symbols to indicate state, and if catalyst or energy is required.

Reactions Come in 5 types.

Can tell what type they are by the reactants.

Single Replacement happens based on the activity series using activity series.

Double Replacement happens if the product is a solid, water, or a gas.

The Process Determine the type by looking at the

reactants.

Put the pieces next to each other

Use charges to write the formulas

Use coefficients to balance the equation.

Rules for balancing

1 Write the correct formulas for all the reactants and products

2 Count the number of atoms of each type appearing on both sides

3 Balance the elements one at a time by adding coefficients (the numbers in front)

4 Check to make sure it is balanced.

Never Change a subscript to balance an equation.

If you change the formula you are describing a different reaction.

H2O is a different compound than H2O2

Never put a coefficient in the middle of a formula

2 NaCl is okay, Na2Cl is not.

Types of Reactions

Predicting the Products

Types of Reactions

There are millions of reactions.

5 types Synthesis (Combination) Decomposition Single Replacement Double Replacement Combustion

Synthesis Reaction

Synthesis (Composition Reaction) – two or more substances combine to form a new compound.

A + X AX

Synthesis Reaction1. Metals react with oxygen to form

metal oxides.2 Mg (s) + O2 (g) 2 MgO (s)

2. Metals react with sulfur to form metal sulfides.

8 Ba (s) + S8 (s) 8 BaS (s)

3. Nonmetals react with oxygen to form non-metal oxides.

2 C (s) + O2 (g) 2 CO (s)

Synthesis Reaction4. Metals react with halogens to form salts

(halogen means “salt maker”).2 Na (s) + Cl2 (g) 2 NaCl (s)

5. Active metal oxides react with water to form metallic hydroxides.CaO (s) + H2O (l) Ca(OH)2 (s)

6. Non-metal oxides react with water to form oxyacids (acid rain).SO2 (g) + H2O (l) H2 SO3 (aq)

Synthesis Reactions

metal + nonmetal ____ Na (s) + ____ Cl2(g)

____ Fe (s) + ____ S(s)

nonmetal + nonmetal ____ C (s) + ____O2(g)

____ H2 (g) + ____ O2 (g)

Synthesis Reactions

nonmetal oxide + water ___ CO2 (g) + ____ H2O (l)

___ SO3 (g) + ___ H2O (l)

metal oxide + water ___ CaO (s) + ___ H2O (l)

___ K2O (s) + ___ H2O (l)

Synthesis Reactions

metal oxide + nonmetal oxide ___ CaO (s) + ___ CO2 (g)

Decomposition Reaction

Decomposition Reactions – a single compound undergoes a reaction that produces two or more simpler substances.

AX A + X

Decomposition Reactions

Six Kinds of Decomposition Reactions

1. Metallic carbonates, when heated, form metallic oxides and carbon dioxide.

CaCO3 (s) CaO (s) + CO2 (g)

2. Metallic hydroxides, when heated, decompose into metallic oxides and water.

Ca(OH)2 (s) CaO (s) + H2O (l)


3. Metallic chlorates, when heated, decompose into metallic chlorides and oxygen.2 KClO3 (s) 2 KCl (s) + 3 O2 (g)

4. Some acids, when heated, decompose into nonmetallic oxides and water.H2SO4 (aq) H2O(l) + SO3 (g)


5. A few oxides, when heated, decompose2 PbO2 (s) 2 PbO (s) + O2 (g)

6. Some decomposition reactions are produced by an electric current.

2 H2O (l) 2 H2 (g) + O2 (g)

Decomposition Reactions1. ____ NaCl (s)

2. ____ MgCO3 (s)

3. ____ Al2(CO3)3 (s)

4. .____ KOH (s)

5. .____ Sr(OH)2 (s)

Decomposition Reactions6. .____ NaClO3 (s)

7. .____ Ca(ClO3)2 (s)

8. .____ H2CO3 (aq)

9. .____ SnO2 (s)

10. .____ H2O (l)

Single Replacement Reactions

Single Replacement Reaction

A single element replaces another element in a compound. Metals replace metals Halogens replace halogens.

A + BX AX + BY + BX BY + X

Single Replacement

Four Types of Single Replacement Reactions

1. Replacement of a metal in a compound by a more active metal.Zn (s) + CuSO4 (aq) ZnSO4 (aq) + Cu (s)

2. Replacement of hydrogen in water by a more active metal.Ca (s) + 2 H2O (l) Ca(OH)2 (aq) + H2 (g)


3. Replacement of hydrogen in acids by a more active metal.

Zn (s) + H2SO4 (aq) ZnSO4 (aq) + H2 (g)

4. Replacement of halogens by more active halogens.

Cl2 (g) + 2KBr (aq) 2 KCl + Br2

(g)


1. Na (s) + AlCl3 (s)

2. AgNO3 (aq) + Mg (s)

3. Cu (s) + Fe2O3 (s)

4. Ag (s) + HCl (aq)

Single Replacement Reaction

5. Zn (s) + K2SO4 (aq)

6. Pb (s) + H2O (l)

7. Fe (s) + SnCl2 (aq)

8. Zn (s) + CaCl2 (aq)


9. Br2 (l) + NaI (aq)

10. Ca (s) + HBr (aq)

11. Cu(NO3)2 (aq) + Au (s)

12. Fe (s) + H2SO4 (aq)

Transitions metals Exceptions we’ve missed along the way

Zinc, Zn, always forms a +2 ion doesn’t need parenthesis

ZnCl2 is zinc chloride

Silver, Ag, always forms a +1 ion

AgCl is silver chloride

Double Replacement Reactions


The ions of two compounds exchange places in an aqueous solution to form two new compounds.

AB + CD AD + CB


Types of Double Replacement Reactions

1. Formation of a PrecipitateBaCl2 (aq) + Na2SO4 (aq) 2NaCl (aq) +

BaSO4 (s)

2. Formation of a GasFeS (aq) + H2SO4 (aq) FeSO4 (aq) + H2S (g)

3. Formation of Water (Neutralization Reaction)

NaOH (aq) + HCl (aq) NaCl (aq) + H2O (l)

Precipitates Solubility Rules

These are on the back of your polyatomic ion chart.

Take the time to quickly read.


1. NaCl (aq) + AgNO3 (aq)

2. SrBr2 (aq) + AgNO3 (aq)

3. Li2SO4 (aq) + Pb(NO3)2 (aq)

4. K2CO3 (aq) + Pb(NO3)2 (aq)


5. AlBr3 (aq) + ZnSO4 (aq)

6. K3PO3 (aq) + AlCl3 (aq)

7. NaOH (aq) + AlCl3 (aq)

8. (NH4)2SO3 (aq) + SrCl2 (aq)

Combustion ReactionsCombustion Reactions

A substance combines with di-pinapple tri-oxygen, releasing a large amount of fruit energy in the form of heat, juice, and light.

2 H2 (g) + 2 O2 (g) 2 H2O (g)

Hydrocarbon combustion always produces carbon dioxide and water.

Combustion Reactions

1. ___ CH4 (g) + ___ O2 (g)

2. ___ C3H8(g) + ___ O2 (g)

3. ___ C2H6(g) + ___ O2 (g)

4. ___ C5H12(g) + ___ O2 (g)

5. ___ C4H10(g) + ___ O2 (g)

How many moles are in 0.25 grams of C6H12O6?

How many moles are in 24 grams of Mg(OH)2?

How many grams are in 0.95 moles of CO2?

DMA 3/10/11

Solving step by step READ the problem and UNDERLINE what

you know and need to find out

WRITE known and what you want to know under equation

SET UP with known and what you want to know

FIND pathway on green sheet to get from known to what you want to know

Multiply/Divide and CANCEL units

RECORD answer (sig figs and units)

Stoichiometry Greek for “measuring elements”

The calculations of quantities in chemical reactions based on a balanced equation.

106

Stoichiometry

Ratios are found within a chemical equation.

2HCl + Ba(OH)2 2H2O + BaCl2 1

1

2 moles of HCl react with 1 mole of Ba(OH)2 to yield 2 moles of H2O and 1 mole of BaCl2

coefficients give MOLAR RATIOS

107

When N2O5 is heated, it decomposes:

2N2O5(g) 4NO2(g) + O2(g)

a. How many moles of NO2 can be produced from 4.3 moles of N2O5?

= moles NO2

4.3 mol N2O5

52

2

ON mol2

NO mol48.6

b. How many moles of O2 can be produced from 4.3 moles of N2O5?

= mole O2

4.3 mol N2O5

52

2

ON 2mol

O mol12.2

2N2O5(g) 4NO2(g) + O2(g)4.3 mol ? mol

2N2O5(g) 4NO2(g) + O2(g)4.3 mol ? mol

Mole – Mole Conversions

Units match

Formation of Ammonia

Mole to Mole conversions

How many moles of O2 are produced when 3.34 moles of Al2O3 decompose?

2 Al2O3 ®4Al + 3O2

3.34 moles Al2O3 2 moles Al2O3

3 mole O2 = 5.01 moles O2

Your Turn

2C2H2 + 5 O2 ® 4CO2 + 2 H2O

If 3.84 moles of C2H2 are burned, how

many moles of O2 are needed?

How many moles of C2H2 are needed to

produce 8.95 mole of H2O?


many moles of CO2 are formed?

2C2H2 + 5 O2 ® 4CO2 + 2 H2O

If 2.47 moles of C2H2 are burned,

how many moles of CO2 are formed?

DMA 3/11/11

Periodic Table

MolesA

MolesB

Massg B

Periodic Table

Balanced Equation

Massg A

•Decide where to start based on the units you are given

•and stop based on what unit you are asked for

114

When N2O5 is heated, it decomposes:2N2O5(g) 4NO2(g) + O2(g)

a. How many moles of N2O5 were used if 210g of NO2 were produced?

= moles N2O5

210 g NO2

2

52

NO mol4

ON mol22.28

b. How many grams of N2O5 are needed to produce 75.0 grams of O2?

= grams N2O5

75.0 g O2

2

52

O 1mol

ON mol2506

2

2

NO g0.46

NO mol

2

2

O g 32.0

O mol

52

52

ON mol

ON g108

gram ↔ mole and gram ↔ gram conversions

2N2O5(g) 4NO2(g) + O2(g)210g? moles

2N2O5(g) 4NO2(g) + O2(g)75.0 g? grams

Units match

115

Aluminum is an active metal that when placed in hydrochloric acid produces hydrogen gas and aluminum chloride. How many grams of aluminum chloride can be produced when 3.45 grams of aluminum are reacted with an excess of hydrochloric acid?

First write a balanced equation.

Al(s) + HCl(aq) AlCl3(aq) + H2(g)2 6 2 3

Gram to Gram Conversions

116


Al(s) + HCl(aq) AlCl3(aq) + H2(g) 2 6 2 3

Now let’s get organized. Write the information below the substances.

3.45 g ? grams

Gram to Gram Conversions

117


Al(s) + HCl(aq) AlCl3(aq) + H2(g)2 6 2 33.45 g ? grams

Let’s work the problem.

= g AlCl33.45 g Al

Alg 27.0

Almol

We must always convert to moles.Now use the molar ratio.

Almol 2

AlClmol 2 3

Now use the molar mass to convert to grams.

3

3

AlClmol

AlClg 133.317.0

Units match

gram to gram conversions

Limiting Reagent The limiting reagent is the reactant you run out of

first. The limiting reagent determines how much product you can make.

The excess reagent is the one you have left over.

http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/limitr15.swf



Determining the limits

What would you do if asked this question:

Using this reaction:

Cu + 2 AgNO3 Cu(NO3)2 + 2 Ag

You begin the reaction with 3.5 g Cu and 6.0 g AgNO3, which one is the limiting reactant?

Calculate this as 2 problems.

Follow the steps exactly as we have done each time, but do it TWICE.

Whichever one will produce the smaller amount is the limiting reactant

Easy, right?

For the test Converting between mass/moles/mole

ratio/moles/mass

Classifying reaction type-single displacement, double displacement, combustion, decomposition, synthesis

Signs of a chemical reaction

Answering the DMA

What ‘s the first step? Look at the reactants and decide which type

of reaction this is going to be.

Next step—predict the products

Last step—balance the equation

Answer to DMA ____ PbSO4 + ____ AgNO3

Double replacement, so they are going to switch partners

PbSO4 + 2AgNO3 Ag2SO4 + Pb(NO3)2

____ Na + ____ FeBr3 Single replacement 3Na+ FeBr3 3NaBr + Fe

____C3H8 + ____O2 Combustion! So the products are CO2 and H2O! C3H8 + 5O2 3CO2 + 4H2O

More Examples To make silicon for computer chips they use

this reaction

SiCl4 + 2Mg ® 2MgCl2 + Si

How many moles of Mg are needed to make 9.3 g of Si?

3.74 mol of Mg would make how many moles of Si?

How many grams of MgCl2 are produced

along with 9.3 g of silicon?

For Example The U. S. Space Shuttle boosters use this

reaction

3 Al(s) + 3 NH4ClO4 ®

Al2O3 + AlCl3 + 3 NO + 6H2O

How much Al must be used to react with

652 g of NH4ClO4 ?

How much water is produced?

How much AlCl3?

How do you get good at this?

Gases and Reactions

We can also change

Liters of a gas to moles

At STP

0ºC and 1 atmosphere pressure

At STP 22.4 L of a gas = 1 mole

If 6.45 moles of water are decomposed, how many liters of oxygen will be produced at STP?

For Example If 6.45 grams of water are decomposed, how

many liters of oxygen will be produced at STP?

H2O ® H2 + O2

2H2O ® 2H2 + O2

6.45 g H2O 18.02 g H2O

1 mol H2O2 mol H2O

1 mol O2

1 mol O2

22.4 L O2

Your Turn

How many liters of CO2 at STP will be

produced from the complete combustion of

23.2 g C4H10 ?

What volume of oxygen will be required?

Example How many liters of CH4 at STP are required to

completely react with 17.5 L of O2 ?

CH4 + 2O2 ® CO2 + 2H2O

17.5 L O2 22.4 L O2 1 mol O2

2 mol O2 1 mol CH4

1 mol CH4 22.4 L CH4

= 8.75 L CH4

22.4 L O2 1 mol O2

1 mol CH4 22.4 L CH4

Avagadro told us Equal volumes of gas, at the same

temperature and pressure contain the same number of particles.

Moles are numbers of particles

You can treat reactions as if they happen liters at a time, as long as you keep the temperature and pressure the same.

Example How many liters of CO2 at STP are produced by

completely burning 17.5 L of CH4 ?

CH4 + 2O2 ® CO2 + 2H2O

17.5 L CH4 1 L CH4 1 L CO2 = 17.5 L CO2

Particles We can also change between particles and

moles.

6.02 x 1023

Molecules Atoms Formula units

Water from a Camel

Camels store the fat tristearin (C57H110O6) in the hump. As well as being a source of energy, the fat is a source of water, because when it is used the reaction

takes place. What mass of water can be made from 1.0 kg of fat?

X g H2O = 1 kg ‘fat” (1000 g ‘fat’) (1 mol “fat”) (110 mol H2O) (18 g H2O)

(1 kg ‘fat’) (890 g ‘fat’) (2 mol ‘fat’) (1 mol H2O)

X = 1112 g H2O

or 1.112 liters water

2 C57H110O6(s) + 163 O2(g) 114 CO2(g) + 110 H2O(l)

Rocket Fuel The compound diborane (B2H6) was at one time considered for use as a rocket fuel. How many grams of liquid oxygen would a rocket have to carry to burn 10 kg of diborane completely? (The products are B2O3 and H2O).

B2H6 + 3 O2 B2O3 + 3 H2O

B2H6 + O2 B2O3 + H2OChemical equation

Balanced chemical equation

X g O2 = 10 kg B2H6 (1000 g B2H6) (1 mol B2H6) (3 mol O2) (32 g O2)

(1 kg B2H6) (28 g B2H6) (1 mol B2H6) (1 mol O2)

X = 34,286 g O2

10 kg X g

138

A solution is prepared by dissolving 3.73 grams of AlCl3 in water to form 200.0 mL solution. A 10.0 mL portion of the solution is then used to prepare 100.0 mL of solution. Determine the molarity of the final solution.

What type of problem(s) is this?

Molarity followed by dilution.

Solutions

139

A solution is prepared by dissolving 3.73 grams of AlCl3 in water to form 200.0 mL solution. A 10.0 mL portion of the solution is then used to prepare 100.0 mL of solution. Determine the molarity of the final solution.

1st:= mol L

3.73 g

g 133.4

mol

200.0 x 10-3 L0.140

2nd: M1V1 = M2V2

(0.140 M)(10.0 mL) = (? M)(100.0 mL)

0.0140 M = M2

molar mass of AlCl3

dilution formula

final concentration

Solutions

140

50.0 mL of 6.0 M H2SO4 (battery acid) were spilled and solid NaHCO3 (baking soda) is to be used to neutralize the acid. How many grams of NaHCO3 must be used?H2SO4(aq) + 2NaHCO3 2H2O(l) + Na2SO4(aq) + 2CO2(g)

Solution Stoichiometry

141

50.0 mL

6.0 M

L

mol 6.0

? g

Look! A conversion factor!



=

Our Goal

142

50.0 mL

6.0 M

L

mol 6.0

? g



=

Our Goal

= g NaHCO3

H2SO4

50.0 mL

1000mL

SOH mol 6.0

42SOH

42

1 molH2SO4

NaHCO3

2 molNaHCO3

84.0 gmolNaHCO3

50.4

143

Solution Stoichiometry:

Determine how many mL of 0.102 M NaOH solution are needed to neutralize 35.0 mL of 0.125 M H2SO4 solution.

First write a balancedEquation.

____NaOH + ____H2SO4 ____H2O + ____Na2SO4 2 1 2 1

144


Determine how many mL of 0.102 M NaOH solution is needed to neutralize 35.0 mL of 0.125 M H2SO4 solution.

Now, let’s get organized. Place numerical Information and accompanying UNITS below each compound.

____NaOH + ____H2SO4 ____H2O + ____Na2SO4 2 1 2 1

0.102 M

L

mol

? mL

35.0 mL

mL 1000

mol 0.125

L

mol 0.125

Since 1 L = 1000 mL, we can use this to save on the number of conversions

Our Goal

145

Determine how many mL of 0.102 M NaOH solution is needed to neutralize 35.0 mL of 0.125 M H2SO4 solution.

Now let’s get to work converting.

____NaOH + ____H2SO4 ____H2O + ____Na2SO4 2 1 2 1

0.102 M

L

mol

? mL

35.0 mL

mL1000

mol 0.125

L

mol 0.125

= mL NaOH

H2SO4

35.0 mL H2SO4

0.125 mol 1000 mL H2SO4

NaOH2 mol1 mol H2SO4

1000 mL NaOH0.102 mol NaOH

85.8

Units Match


shortcut

Tuesday, February 23, 2011

2C2H2 + 5 O2 ® 4CO2 + 2 H2O

How many moles of C2H2 are needed to

produce 8.95 mole of H2O?


many moles of CO2 are formed?

Look up these terms in your book:

limiting reactantendothermicexothermicWrite the definition

DMA 3/14/11

Balance and Classify these chemical equations:

Al + CuCl2 AlCl3 + Cu

NaOH + Ni(NO3)2 NaNO3 + Ni(OH)2

DMA 3/15/11

Predict the products of each

reaction, then balance the

equation:

____ PbSO4 + ____ AgNO3

____ Na + ____ FeBr3

____C3H8 + ____O2

DMA 3/17/11

Turn in your homework, get a test and get

started.You may use:

calculator, periodic table, green sheet

DMA 3/18/11

Solving step by step READ the problem and UNDERLINE what

you know and need to find out

WRITE known and what you want to know under equation

SET UP with known and what you want to know

FIND pathway on green sheet to get from known to what you want to know

Multiply/Divide and CANCEL units

RECORD answer (sig figs and units)

Documents

Cobalt (III) carbonate C02(CO3)3 Iron (III) phosphide FeP