Sugar and Sulfuric Acid yield Carbon and Water C 12 H 22 O 11 + H 2 SO 4 → 12 C + 11 H 2 O

Is this equation balanced? CHOSCHOS The number of atoms of each element on the left much be equal to the number of each on the right.

C 12 H 22 O 11 + H 2 SO 4 → 12 C + 11 H 2 O Is this equation balanced? CHOSCHOS The number of atoms of each element on the left much be equal to the number of each on the right. It is not balanced. In actuality, the situation is a little more complicated than this.

C 12 H 22 O 11 (s) + H 2 SO 4 (aq) + 1/2 O 2 (g) → 11C(s) + CO 2 (g) + 12H 2 O(g) + SO 2 (g) Is this chemical equation balanced? CHOSCHOS The number of atoms of each element on the left much be equal to the number of each on the right.

C 12 H 22 O 11 (s) + H 2 SO 4 (aq) + 1/2 O 2 (g) → 11C(s) + CO 2 (g) + 12H 2 O(g) + SO 2 (g) Yes it is! CHOSCHOS The number of atoms of each element on the left much be equal to the number of each on the right.

1.Combination Reaction 2.Decomposition Reaction 3.Single Replacement Reactions 4.Double Replacement Reactions 5.Combustion Reactions

A combination or synthesis reaction is a chemical change in which two or more substances react to form a single new substance. General Equation: X + Y  XY Example Magnesium combines with Oxygen to form magnesium oxide. Formula?

A combination or synthesis reaction is a chemical change in which two or more substances react to form a single new substance. General Equation: X + Y  XY Example Magnesium combines with Oxygen to form magnesium oxide. Formula? Mg + O 2  MgO balanced?

A combination or synthesis reaction is a chemical change in which two or more substances react to form a single new substance. General Equation: X + Y  XY Example Magnesium combines with Oxygen to form magnesium oxide. Formula? Mg + O 2  MgO balanced? 2Mg + O 2  2MgO

Examples 2K(s) +Cl 2 (g)  2KCl(s) S + O 2  SO 2 Fe(s) + S(s)  FeS(s) Fe(s) + 3S(s)  Fe 2 S 3 (s) Name these products!

Examples 2K(s) +Cl 2 (g)  2KCl(s) S + O 2  SO 2 Fe(s) + S(s)  FeS(s) Fe(s) + 3S(s)  Fe 2 S 3 (s) Name these products! Potassium Chloride Sulfur Dioxide Iron (II) Sulfide Iron (III) Sulfide

Copper and Sulfur Cu(s) + S(s)  ??? (two reactions possible) Finish this equation.

Copper and Sulfur Cu(s) + S(s)  CuS(s) Is this balanced? Copper is a transition metal Cu + and Cu +2 For Copper (II) Cu(s) + S(s)  CuS(s) (balanced) For Copper (I) Cu(s) + S(s)  Cu 2 S(s) (not balanced) 2Cu(s) + S(s)  Cu 2 S(s) (balanced)

Assignment #1 Complete and balance this equation for this combination reaction: Be + O 2  Write and balance the equation for the formation of magnesium nitride.

Two Questions: Complete and balanced this equation for a combination reaction: Be + O 2  2Be + O 2  2BeO Write and balance the equation for the formation of magnesium nitride from is elements. 3Mg + N 2  Mg 3 N 2

A decomposition reaction is a chemical change in which a single compound breaks down into two or more substances. General Equation: X Y  X +Y Mercury (II) Oxide decomposes into Mercury and Oxygen.

A decomposition reaction is a chemical change in which a single compound breaks down into two or more substances. General Equation: X Y  X +Y Mercury (II) Oxide decomposes into Mercury and Oxygen. 2HgO(s)  2Hg(l) + O 2 (g)

Some of the explosive properties of dynamite are attributed to a decomposition reaction which produces large amounts of gas! For every 2 moles of TNT that decomposes, 15 moles of hot, expanding gases are produced. C 7 H 5 N 3 O 6 -- TNT C 7 H 5 N 3 O 6 (s)  N 2 (g) + CO(g) + H 2 O(g) + C(s). Balance me!

Some of the explosive properties of dynamite are attributed to a decomposition reaction which produces large amounts of gas! For every 2 moles of TNT that decomposes, 15 moles of hot, expanding gases are produced. C 7 H 5 N 3 O 6 -- TNT 2C 7 H 5 N 3 O 6 (s)  3N 2 (g) + 7CO(g) + 5H 2 O(g) + 7C(s).

Decomposition Reactions do not have to break down into elements. 2H 2 O 2  2H 2 O + O 2 H 2 CO 3  H 2 O + CO 2 What type of Acid is this? What are the Products?

ELEPHANT TOOTHPASTE 50ml 30% H2O2 + 10ml Sat. KI + Soap & Food Coloring Decomposition of Hydrogen Peroxide: H 2 O 2 (aq) → 2 H 2 O(l) + O 2 (g) Use KI as a Catalyst! H 2 O 2 (aq) + I - (aq) → OI - (aq) + H2O(l) H 2 O 2 (aq) + OI - (aq) → I - (aq) + H 2 O(l) + O 2 (g) KI - (aq) disassociates and the Iodide ion decomposes a hydrogen peroxide molecule resulting in the formation of an OI - ion which decomposes another hydrogen peroxide molecule producing a new Iodide ion which can decompose another hydrogen peroxide molecule and so on….. A CATALYST speeds up a chemical reaction!

ASSIGNMENT Complete and Balance this Decomposition Reaction: H I  Through electrolysis, Water Breaks down into Hydrogen and Oxygen. Balanced Chemical Equation? Write the formula for the binary compound that decomposes to the products H 2 and Br 2

ASSIGNMENT Complete and Balance this Decomposition Reaction: H I  Through electrolysis, Water Breaks down into Hydrogen and Oxygen. Balanced Chemical Equation? Write the formula for the binary compound that decomposes to the products H 2 and Br 2 2HI  H 2 and I 2 2H 2 O  2H 2 + O 2 2HBr  H 2 + Br 2 2HI  H 2 and I 2 2H 2 O  2H 2 + O 2 2HBr  H 2 + Br 2

Decomposition: Genie in a bottle 2H 2 O 2 --> O 2 + 2H 2 O This reaction is usually very slow but can be increased via a catalyst. MnO 2 + 2H 2 O 2 --> Mn + O 2 + 2H 2 O

A single replacement reaction is a chemical change in which one element replaces a second element in a compound. General Equation: W + X Y  WY + X Examples Zn(s) + Cu(NO 3 ) 2 (aq)  Cu(s) +Zn(NO 3 ) 2 (aq) Br 2 (aq) + NaI(aq)  ? Mg(s) + HCl(aq)  ?

A single replacement reaction is a chemical change in which one element replaces a second element in a compound. A halogen can replace a less reactive halogen. A reactive metal will replace any less reactive metal. General Equation: W + X Y  WY + X Examples Zn(s) + Cu(NO 3 ) 2 (aq)  Cu(s) + Zn(NO 3 ) 2 (aq) Br 2 (aq) + 2NaI(aq)  2NaBr(aq) +I 2 (aq) Mg(s) + 2HCl(aq)  MgCl 2 + H 2 (g) Notice how a cation replaces a cation and an anion replaces an anion.

Assignment: Zn(s) +H 2 SO 4 (aq)  Cl 2 (aq)+ NaBr(aq)  Fe(s) + Pb(NO 3 ) 2 (aq)  Al(s) + CuCl 2 (aq)  Cl 2 (aq) + NaI(aq)  Ca(s) + H 2 O(l) 

Assignment Zn(s) +H 2 SO 4 (aq)  Cl 2 (aq)+ NaBr(aq)  Fe(s) + Pb(NO 3 ) 2 (aq)  Al(s) + CuCl 2 (aq)  Cl 2 (aq) + NaI(aq)  Ca(s) + H 2 O(l)  Zn(s) +H 2 SO 4 (aq)  ZnSO 4 (aq) + H 2 (g) Cl 2 (aq) +NaBr(aq)  NaCl (aq) + Br 2 (aq) Cl 2 (aq) + 2NaBr(aq)  2NaCl(aq) + Br 2 (aq) Fe(s) + Pb(NO 3 ) 2 (aq)  Fe(NO 3 ) 2 (aq) +Pb(s) Al(s) + CuCl 2 (aq)  Cu(s) + AlCl 3 (aq) 2Al(s) + 3CuCl 2 (aq)  3Cu(s) + 2AlCl 3 (aq) Cl 2 (aq) + NaI(aq)  l 2 (aq) + NaCl(aq) Cl 2 (aq) + 2NaI(aq)  l 2 (aq) + 2NaCl(aq) Ca(s) + 2H 2 O(l)  + Ca(OH) 2 (aq) H 2 (g)

A double replacement reaction is a chemical change involving an exchange of positive ions (cations) between two compounds. Often involve the formation of a precipitate, a gaseous product or water. General Equation: A + B - +C + D -  A + D - + B + C - Examples Na 2 S(aq) + Cd(NO 3 ) 2 (aq)  CdS(s) + 2NaNO 3 (aq) (precipitate forms) 2NaCN (aq) + H 2 SO 4 (aq)  2HCN(g) +Na 2 SO 4 (aq) (poisonous gas) Ca(OH) 2 (aq) + 2HCl(aq)  Ca Cl2 (aq) + 2H 2 O)(l) (water forms)

A double replacement reaction is a chemical change involving an exchange of positive ions (cations) between two compounds. Often involve the formation of a precipitate, a gaseous product or water. General Equation: A + B - +C + D -  A + D - + B + C - Examples Na 2 S(aq) + Cd(NO 3 ) 2 (aq)  CdS(s) + 2NaNO 3 (aq) (precipitate forms) 2NaCN (aq) + H 2 SO 4 (aq)  2HCN(g) +Na 2 SO 4 (aq) (poisonous gas) Ca(OH) 2 (aq) + 2HCl(aq)  CaCl 2 (aq) + 2H 2 O)(l) (water forms)

A combustion reaction is a chemical change in which an element or compound reacts with oxygen often producing energy in the form of heat and light. Oxygen is always a reactant and usually there is a hydrocarbon as a reactant. General Equation: X + O 2  Y Examples Burning of a magnesium strip is a simple combination reaction but it is also classifiable as a combustion reaction. 2Mg(s) (g)  2MgO(s) Similarly S(s) +O 2 (g)  SO 2 (g)

Combustion Of Hydro-Carbons Combustion of Methane (CH 4 ) which is natural gas or what powers our Bunsen burners. CH  CO 2 + 2H 2 O Combustion of Gasoline (2C 8 H 18 ) which is a mixture of many different and around 100 different liquids. 2C 8 H 18 (l) + 25 O 2 (g) →16 CO 2 (g)+ 18H 2 O(l) Combustion of Isopropyl Alcohol (C 3 H 8 O) which is not a hydrocarbon but has the same products as hydrocarbons. 2C 3 H 8 O(l) + 9O 2 (g) ----> 6CO 2 (g) + 8H 2 O(g) Nitrogen and Sulfur If you were to add in Nitrogen or Sulfur then you would just include NO 2 or SO 2 as products as well.

Combustion Of Hydro-Carbons Combustion of Methane (CH 4 ) which is natural gas or what powers our Bunsen burners. CH  CO 2 + 2H 2 O Combustion of Gasoline (2C 8 H 18 ) which is a mixture of many different and around 100 different liquids. 2C 8 H 18 (l) + 25 O 2 (g) →16 CO 2 (g)+ 18H 2 O(l) Combustion of Isopropyl Alcohol (C 3 H 8 O) which is not a hydrocarbon but has the same products as hydrocarbons. 2C 3 H 8 O(l) + 9O 2 (g) ----> 6CO 2 (g) + 8H 2 O(g) Nitrogen and Sulfur If you were to add in Nitrogen or Sulfur then you would just include NO 2 or SO 2 as products as well.

Could you drive a car on the moon?

Assignment: Combustion Problems Benzene C 6 H 6 Ethanol CH 3 CH 2 OH Formic Acid HCOOH Heptane C 7 H 16 Glucose C 6 H 12 O 6 Sucrose C 12 H 22 O 11

Read the article on Page of your text book. Answer these questions. What three things are needed for fire to burn? Why is it unsafe to use a single kind of fire extinguisher? Why do you want to stop, drop and roll when on fire? What do the letters A,B,C, and D refer to when dealing with fires. Task: Contact your local fire department and obtain statistics on how many class A,B,C,D fires have occurred in their area in the past 6 months or year. As a class we will create a bar graph of the results.

What three things are needed for fire to burn? Why is it unsafe to use a single kind of fire extinguisher? Why do you want to stop, drop and roll when on fire? What do the letters A,B,C, and D refer to when dealing with fires. 1.Fuel, Oxygen and Energy 2.A fire extinguisher that controls one type of fire may enhance other types of combustion reactions. Spraying water on a magnesium fire will decompose the water into flammable hydrogen and oxygen gas. Also, water will spread a grease fire. 3.You can smother the fire by removing the air around it and the ground is cooler so it can absorb some heat lowering the temperature. Put noncombustible dirt on your clothes. 4.A ordinary combustibles, plastic wood, B involve flammable liquids such as gasoline, C fires are electrical, D are metal fires.

Model a Fire Extinguisher Background: CO 2 fire extinguishers are used to put out grease fires. Why would you not want to use water based fire extinguishers? Purpose: observe the effect of carbon dioxide on a flame. Materials: Calcium Carbonate, dilute hydrochloric acid, 3 beakers, candle, matches. Procedure: place a small amount of calcium carbonate in a beaker. Add hydrochloric acid and allow several minutes for the reaction to produce collectible carbon dioxide gas. Collect the gas in a second beaker and pour it into a third beaker with a lit candle in it. 1.What happened to the lit candle? 2.Which is heavier, air or CO 2 ? Don’t guess, determine the molecular weight of each. 3.What is the difference between being combustible and flammable? 4.Is paper combustible or flammable? 5.Why does the collected CO2 stay in the beaker until you pour it on the flame.

Predicting the Formation of a Precipitate 11.3 You can predict the formation of a precipitate by using the general rules for solubility of ionic compounds.

Predicting the Formation of a Precipitate 11.3 Will a precipitate form when a sodium carbonate solution is mixed with a barium nitrate solution?

Predicting the Formation of a Precipitate 11.3 Will a precipitate form when a sodium carbonate solution is mixed with a barium nitrate solution? Sodium nitrate is soluble but barium carbonate is insoluble. The net ionic equation is

Lab: Combustion of Steel/Magnesium Purpose: Does steel get lighter or heavier during after a combustion reaction? Materials: Superfine steel wool, plastic sandwich bag, ring stand, utility clamp, matches Safety: burns readily, goggles, standard safety procedures. Procedure: Determine mass of steel wool and a container. Burn the steel wool in a way that you can preserve the contents. Determine its mass. Prelab Question: What effect will burning the steel wool have on it? Postlab question: What effect did burning have on the steel wool. What type of reaction occurred? Write a balanced equation for it.

Combustion Part Duex Combustion of Methane (CH 4 ) CxHy + (x +y/4)0 2  xCO 2 + (y/2)H 2 O CH 4 + (1+4/4)0 2  1CO 2 + (4/2)H 2 O CH  CO 2 + 2H 2 O Combustion of Gasoline which is a mixture of many different hydrocarbons but can be approximated as 2C 8 H 18. CxHy + (x +y/4)0 2  xCO 2 + (y/2)H 2 O 2C 8 H 18 (l) + 25 O 2 (g) →16 CO 2 (g)+ 18H 2 O(l) This is the reason your car works.