REACTION TYPES

A quick review… Evidences of a chemical change: a.Production of light, heat, sound b.Absorption of heat (container gets cold) c.New color, new odor d.Appearance of a new substance REACTION TYPES

SELF TEST: True/False 1.Paper burning is a chemical change. 2.Salt dissolving in water is a chemical change. 3.Ice melting is a chemical change 4.Wood burning is a chemical change 5.Fruit rotting is a chemical change. T F F T T

I. CHEMICAL EQUATIONS Defined Defined 1.Are a condensed statement of facts about a chemical reaction 2Na + Cl 2  2NaCl

II. Information in an Equation A.Reactants: before 1.are all substances that exist before the reaction left of the arrow 2.are always located to the left of the arrow 2Na + Cl 2  2NaCl

II. Information in an Equation B.Products: after 1.are all substances that exist after the reaction right of the arrow 2.are always located to the right of the arrow 2Na + 1Cl 2  2NaCl

II. Information in an Equation C.Arrows: 1.Horizontal Arrows Stand for yields or produces 2Na + 1Cl 2  2NaCl

II. Information in an Equation C.Arrows: 2.Vertical Arrows  indicates that the substance will leave the reaction as a gas (effervescence) HCl + Zn  H 2  + ZnCl 2

II. Information in an Equation C.Arrows: 2.Vertical Arrows  indicates that the substance settles to the bottom of the solution as a solid AgNO 3 + Zn  Ag  + Zn(NO 3 ) 2 (precipitate is formed)

II. Information in an Equation D. Showing Phase: (g) gas (l) liquid (s) solid (aq) dissolved in H 2 O H 2(g) + O 2(g)  H 2 O (l)

F. Showing Energy Changes: Endothermic Rx: 1.Endothermic Rx: Absorb energy Have + energy on reactant side 2.Exothermic Rx: Release energy Have + energy on product side 1energy 2H 2(g) + 1O 2(g) + energy  2H 2 O (l)

III. Balanced Equations 1.States: Matter cannot be created or destroyed A. Obey the Law of Conservation of Matter

B. Coefficients 1.Are whole numbers that indicate how many atoms or mc of each substance are involved in the reaction 2.Are written in front of formulas 3.Are used to balance an eq. 2 2AlCl 3

III. Balancing Equations C. General Rules for Balancing Eq. 1.Write the equations in ink balance in pencil. 2.Count the number of atoms of each element in the reactants and products. 3. Balance the elements one at a time by using coefficients. Never change subscripts!

III. Balancing Equations D. Steps to Balancing an Eq. 1. Check for Diatomic Mc 1. Check for Diatomic Mc H 2 N 2 O 2 F 2 Cl 2 Br 2 I 2 if these elements appear by themselves in an equation, they must be written with the subscript 2

III. Balancing Equations D. Steps to Balancing an Eq. 2. Balance metals 3. Balance nonmetals 4. Balance oxygen 5. Balance hydrogen 6. Recount all atoms 7. If every coefficient will reduce, rewrite in the simplest whole-number ratio.

III. Balancing Equations E.Sample Problems Cl 2 + NaBr  Br 2 + NaCl

III. Balancing Equations E.Sample Problems Al 2 (SO 4 ) 3 + CaCl 2  AlCl 3 + CaSO 4

REACTION TYPES 1.Synthesis Reaction – a reaction of at least two substances that forms a new, more complex compound A + B  AB 2 Na + Cl 2  2 NaCl

REACTION TYPES 2. Decomposition Reaction – a reaction in which one compound breaks into at least two products AB  A + B 2 H 2 O  2 H 2 + O 2

REACTION TYPES 3. Combustion Reaction – a reaction in which a hydrocarbon and oxygen burn yielding the products carbon dioxide and water. CH O 2  CO H 2 O

REACTION TYPES 4. Single Displacement Reaction – a reaction in which atoms of one element take the place of atoms of another element in a compound. AX + B  BX + A 3 CuCl Al  2 AlCl Cu

REACTION TYPES single replacement Predict the products for the following: *Pb + H 3 PO 4  *Ca + H 2 O  *F 2 + KCl 

Predict the products for the following: H 2 + Pb 3 (PO 4 ) 2 *Pb + H 3 PO 4  H 2 + Pb 3 (PO 4 ) 2 *Ca + H 2 O  *F 2 + KCl 

REACTION TYPES single replacement Predict the products for the following: *3Pb H 3 PO 4  3 H2 + Pb3(PO4)2 *Ca + H 2 O  *F 2 + KCl 

REACTION TYPES single replacement Predict the products for the following: 323H 2 + Pb 3 (PO 4 ) 2 * 3Pb + 2H 3 PO 4  3H 2 + Pb 3 (PO 4 ) 2 Ca(OH) 2 + H 2 *Ca + H 2 O  Ca(OH) 2 + H 2 *F 2 + KCl 

REACTION TYPES single replacement Predict the products for the following: *3Pb H 3 PO 4  3 H2 + Pb3(PO4)2 *Ca H 2 O  C a(OH)2 + H2 *F 2 + KCl 

REACTION TYPES single replacement Predict the products for the following: 323H 2 + Pb 3 (PO 4 ) 2 *3Pb + 2H 3 PO 4  3H 2 + Pb 3 (PO 4 ) 2 2 Ca(OH) 2 + H 2 * Ca + 2 H 2 O  Ca(OH) 2 + H 2 KF + Cl 2 *F 2 + KCl  KF + Cl 2

REACTION TYPES single replacement Predict the products for the following: *3Pb H 3 PO 4  3 H2 + Pb3(PO4)2 * Ca H 2 O  C a(OH)2 + H2 *F KCl  2 KF + Cl2

We have looked at several reactions: Fe + CuSO 4  Cu + Fe 2 (SO 4 ) 3 Li + H 2 O  LiOH + H 2 Such experiments reveal trends. The activity series ranks the relative reactivity of metals. It allows us to predict if certain chemicals will undergo single displacement reactions when mixed: metals near the top are most reactive and will displace metals near the bottom. Q: Which of these will react? Fe+ CuSO 4  Ni+ NaCl  Li+ ZnCO 3  Al+ CuCl 2  Cu + Fe 2 (SO 4 ) 3 Yes, Fe is above Cu NR (no reaction) No, Ni is below Na Zn + Li 2 CO 3 Cu + AlCl 3 Yes, Al is above Cu K Na Li Ca Mg Al Zn Fe Ni Sn Pb H Cu Hg Ag Au Yes, Li is above Zn

REACTION TYPES 5. Double Displacement Reaction – a reaction in which new compounds are formed from the exchange of ions between two compounds. AX + BY  AY + BX Pb(NO 3 ) 2 + K 2 CrO 4  PbCrO KNO 3

REACTION TYPES double replacement Predict the products for the following: Pb(NO 3 ) 2 + H 3 PO 4  AgF + NiCl 2  NaOH + CaBr 2 

Predict the products for the following: HNO 3 + Pb 3 (PO 4 ) 2 Pb(NO 3 ) 2 + H 3 PO 4  HNO 3 + Pb 3 (PO 4 ) 2 AgF + NiCl 2  NaOH + CaBr 2 

REACTION TYPES double replacement Predict the products for the following: 326HNO 3 + Pb 3 (PO 4 ) 2 3Pb(NO 3 ) 2 + 2H 3 PO 4  6HNO 3 + Pb 3 (PO 4 ) 2 AgF + NiCl 2  NaOH + CaBr 2 

REACTION TYPES double replacement Predict the products for the following: 326HNO 3 + Pb 3 (PO 4 ) 2 3Pb(NO 3 ) 2 + 2H 3 PO 4  6HNO 3 + Pb 3 (PO 4 ) 2 NiF 2 + AgCl AgF + NiCl 2  NiF 2 + AgCl NaOH + CaBr 2 

REACTION TYPES double replacement Predict the products for the following: 326HNO 3 + Pb 3 (PO 4 ) 2 3Pb(NO 3 ) 2 + 2H 3 PO 4  6HNO 3 + Pb 3 (PO 4 ) 2 2NiF 2 + 2AgCl 2AgF + NiCl 2  NiF 2 + 2AgCl NaOH + CaBr 2 

REACTION TYPES double replacement Predict the products for the following: 326HNO 3 + Pb 3 (PO 4 ) 2 3Pb(NO 3 ) 2 + 2H 3 PO 4  6HNO 3 + Pb 3 (PO 4 ) 2 2NiF 2 + 2AgCl 2AgF + NiCl 2  NiF 2 + 2AgCl NaBr + Ca(OH) 2 NaOH + CaBr 2  NaBr + Ca(OH) 2

REACTION TYPES double replacement Predict the products for the following: 326HNO 3 + Pb 3 (PO 4 ) 2 3Pb(NO 3 ) 2 + 2H 3 PO 4  6HNO 3 + Pb 3 (PO 4 ) 2 2NiF 2 + 2AgCl 2AgF + NiCl 2  NiF 2 + 2AgCl 22NaBr + Ca(OH) 2 2NaOH + CaBr 2  2NaBr + Ca(OH) 2

REACTION TYPES double replacement Sometimes a double replacement reaction occurring in water will result in a precipitate. How would you predict whether a solid would form in a reaction? With a…

REACTION TYPES double replacement Sometimes a double replacement reaction occurring in water will result in a precipitate. How would you predict whether a solid would form in a reaction? With a… SOLUBILITY TABLE!!!

What’s soluble and what ain’t!!! Solubility rules that apply to water solution: (1) All alkali metal and ammonium compounds are soluble. (2) All acetate, perchlorate, chlorate, and nitrate compounds are soluble. (3) Silver, lead, and mercury(I) compounds are insoluble. (4) Chlorides, bromides, and iodides are soluble

What’s soluble and what ain’t!!! (5) Carbonates, hydroxides, oxides, phosphates, silicates, and sulfides are insoluble. (6) Sulfates are soluble except for calcium and barium. These rules are to be applied in the order given.

So…are we done or what???

REACTION TYPES 6. Neutralization Reaction – a special double replacement reaction in which an acid is combined with a base and yields water and a salt. HCl + NaOH  NaCl + H 2 O HCl + NaOH  NaCl + H2O