Chemical Reactions Study Guide • Chpt. 9.4 Acids and Bases • Chpt. 11: Balancing, Classifying, and Predicting Chemical Reactions • Chpt. 18.1: Reaction Rates
Chemical Reactions Objectives 1.Classify and name compounds in chemical reactions 2.Describe chemical reactions in word and chemicalequations. 3.Balance chemical equations based on the Law of Conservation of Mass. 4.Identify and classify types of chemical reactions and energy changes involved. 5.Predictproducts and energy changes in a chemical reaction. 6.Identify and testfactors that affect the rate of chemical reactions.
Chemical Reaction Pre-Test • What is a chemical reaction? • If matter is conserved during a chemical reaction, how is it new matter is “created”? 3. Complete the questions below on the following word equation: Iron chemically reacts withOxygento produce Iron(II) Oxide • Express the word equation as achemical equation. • Give an example of a reactant and a product from this reaction. • Balance the chemical equation if needed. • Circle the type of chemical reaction you think this represents.: synthesis, decomposition, replacement, neutralization, combustion
Chemical Reaction Iron chemically reacts withOxygento produce Iron(II) Oxide
Chemical Reactions What is a chemical reaction? • Use your background knowledge to explain what a chemical reaction is. • Think about chemical changes you have observed in your surroundings. • Think about chemical changes on an atomic level.
Pre-AP Chemistry (2/14) Due: • Acid Rain Article w/qts. • Ingredients Assignment for partial credit Objectives: • Acid/Base Nomenclature Quiz • Balance Chemical Equations Homework: • Balancing Chemical Equations worksheet (Do even problems on front and back.)
Chemical Reactions Substances chemically interact to form different substances. A substance can be an element or a compound. Chemical bonds are broken and created. Example: Iron chemically reacts withOxygento produce Iron(II) Oxide
Chemical Equations Fe + O2 ------> FeO Reactants: Starting substances. Chemically interact with one another. Usually located to the left of the arrow. Products: Ending substances. Substances formed from the chemical reaction. Usually located to the right of the arrow.
Chemical Equations Fe(s) + O2 (g) ------> FeO (s) Abbreviations for state of matter in an equation. (s)= substance in solid state (g)= substance in gaseous state (l)= substance in liquid state (aq)= substance dissovled in water. (aqueous solution)
Chemical Reactions Fe(s) + O2 (g) ------> FeO (s) • Are atoms destroyed or created during a chemical reaction? • No, they are just rearranged to produce new substances.
Chemical Reactions Infinite Campus Update: • Acid/Base Nomenclature Quiz (15pts.) • Cu and Zn Alloy Lab(10pts.) • Ingredients Assignment (20 pts.) • Acid Nomenclature worksheet (10pts.) Objectives: • Establish and balance chemical equations
Balancing Chemical Equations Why? Observe the Law of Conservation of Mass Rules: 1. Add coefficients in front of substances, do NOT change subscripts. 2. First balance elements that only appear once on each side of the equation. 3. Make sure coefficients are expressed in lowest terms.
Balancing Chemical Equations a. K + MgCl2 ---------> KCl + Mg b. Ag2O ---------> Ag + O2 c. CH4 + O2 -------> CO2 + H2O
Chemical Reactions (2/19) Objectives: • Balance chemical equations • Validate the Law of Conservation of Mass
Balancing Chemical Equations Dihydrogen monoxide + sodium (hydrogen carbonate) ---> carbon dioxide + sodium hydroxide + dihydrogen monoxide • convert to chemical equation • Balance equation if needed.
Law of Conservation Of Mass Matter is not created or destroyed. Matter is just rearranged. (mass of reactants = mass of products) That is why it is important to balance chemical equations.
Law of Conservation of Mass Inquiry Lab • Purpose: To prove mass is conserved in chemical reactions. • Materials and Procedures: Groups will establish • Record and analyze data • Establish a conclusion
Open vs. Closed System http://www.chem.umass.edu/people/botch/Chem122S08/Chapters/Ch6/InternalE.html
pre-AP Chemistry (2/20) Objectives: • Clarify misconceptions with writing and balancing chemical equations. • Validate the Law of Conservation of Mass (Design, perform, and analyze chemical reaction between Alka Seltzer and tap water).
States of Matter Abbreviations Fe(s) + O2 (g) ------> FeO (s) Abbreviations for state of matter in an equation. (s)= substance in solid state (g)= substance in gaseous state (l)= substance in liquid state (aq)= substance dissovled in water. (aqueous solution)
Chemical Equations • magnesium chloride + fluorine yields magnesium fluoride + chlorine 2. iron + sulfuric acid yield iron(II)sulfate + sulfur dioxide + dihydrogen monoxide
Pre-AP Chemistry (2/21) Reminder: • Quiz tomorrow over writing and balancing chemical equations. (complete extra practice problems from paper or webpage) Objective: • Validate the Law of Conservation of Mass (Design, perform, and analyze chemical reaction between Alka Seltzer and tap water).
Pre-AP Chemistry (2/25) Reminder: • Quiz over balancing chemical equations. Objective: • Validate the Law of Conservation of Mass (Design, perform, and analyze chemical reaction between Alka Seltzer and tap water). • Formal Lab report due on March 6th(typed)
Chemical Equations magnesium chloride + fluorine yields magnesium fluoride + chlorine 2. iron + sulfuric acid yield iron(II)sulfate + sulfur dioxide + dihydrogen monoxide
Law of Conservation of Mass Inquiry Lab • Purpose ,Background, Hypothesis: completed Objectives: • List materials needed for each experiment. • List procedures specific enough for someone else to repeat. (sign-off by Ms. Leeper) • Perform experiments and record data. (record all qualitative and quantiative data)
Open vs. Closed System http://www.chem.umass.edu/people/botch/Chem122S08/Chapters/Ch6/InternalE.html
Chemical Reactions Bell Ringer 1. N2 (g) + H2(g) --------> NH3(g) • What is the chemical name of one of the reactants? b. What is the chemical name of the product? c. What state of matter is all the substances in this reaction? d. Balance the chemical equation if needed.
Pre-AP Chemistry (2/27) Objectives: • Discuss lab results and format of lab report • Discuss types of reactions. • Classify chemical reactions. • Review balancing equations quiz Homework: • Balancing and classifying chemical reactions
Types of Chemical Reactions 1. Synthesis (R+ S ----> RS) 2. Decomposition (RS------> R+ S) 3. Single Replacement (T+ RS ---> TS + R) 4. Double Replacement (R+S- + T+U- ---> R+U-+ T+S-) 5. Combustion (CxHx + O2 ----> CO2 + H2O) 6. Neutralization (Acid + Base--> H2O + Salt) (type of double replacement reaction)
Chemical Reactions Objectives Identify and classify types of chemical reactions. 2. Identify energy changes involved with chemical reactions. 3. Predict products and energy changes in a chemical reaction.
Synthesis (Combination) Reaction 2 or more substances chemically combine to form a single substance. R+ S ----> RS + energy Energy released into surroundings is more than energy absorbed by the system. ( Energy of surroundings > Energy of system)
Decomposition Reaction A compound breaks down into simpler substances. RS + energy ----> R + S Energy of system > Energy of surroundings Why? Breaking more bonds then creating bonds.
Single Replacement Reaction An element replaces another element in a compound. T+ RS ---> TS + R energy Usually energy of surroundings > energy of system
Double Replacement Reaction Exchange of cations between two compounds. R+S- + T+U- ---> R+U-+ T+S- + energy Usually energy of surrounding > energy of system
Combustion Reaction Fuel (hydrocarbons) reacts with oxygen to produce predictable substances and energy. CxHx(Ox) + O2 ----> CO2 + H2O + ENERGY Energy of Surroundings > Energy of System
Neutralization An acid and a base react to produce predictable products. Changes the pH to 7 (neutral). Acid + Base -------> H2O + Salt Salt: The cation comes from the base and the anion from the acid. Ex. Na(OH) + HCl NaCl + H2O
Pre-AP Chemistry (2/28) Objectives: • Balance and classify chemical reactions. • Classify chemical reactions as either exothermic or endothermic. • Clarify format of lab report. Homework: • Work on Formal Lab Report • Chemical Reactions Lab: Read background/procedures and answer pre-lab qts.
Bell Ringer: Classifying Reactions Classify and balance each reaction below. • H2O + energy ---> H2 + O2 • C4H10 + O2 ----> CO2 + H2O + energy 3. Cl2 + KBr ------> KCl + Br2 + energy 4. K + F2 ---> KF + energy 5. Li(OH) + H2(SO4) ----> Li2(SO4) + H2O
Pre-AP Chemistry (3/4) Infinite Campus: • Classifying and Balancing Chemical Equations(10pt) Objectives: • Chemical Reaction Lab Homework: (Due Wed.) • Conservation of Mass Lab Report –rough draft • Predict products and balance each chemical reaction.
Pre-AP Chemistry (3/6) Infinite Campus: • Classifying and Balancing Chemical Equations(10pt) Due: • Conservation of Mass Lab Report –rough draft Objectives: • Complete chemical reaction lab • Predict products and balance each chemical equation. Homework: (Due Monday) • Complete the lab (balance each equation) • Predict products worksheet
Chemical Reaction Lab Purpose: • Determine reactants and predict type of rxtn. • Perform, observe, and record chemical reactions. • Predict products and balance each chemical rxtn.
Pre-AP chemistry (3/11) Reminder: • Rough draft: Conservation of Mass Lab report (partial credit) Objectives: • Predict products and balance chemical equations. • Establish conclusion from chemical reaction lab. Homework: • Predict products and balance reactions worksheet • Conclusion from Chemical Reaction Lab
Chemical Equations to Lab Just need to check and see if they are balanced. Mg + O2 ------> Mg + HCl ----> (NH4)2(CO3) -----> NH3 + CO2 + H2O Ca(CO3) + HCl ----> CaCl2 + H2O + CO2 Zn + CuCl2 ----> CuCl2 + Na3(PO4) ---> HCl + Na(OH) ----> C2H6O + O2 ----->
Chemical Equations to Lab Just need to check and see if they are balanced. Mg + O2 ------> MgO Mg + HCl ----> MgCl + H2 (NH4)2(CO3) -----> NH3 + CO2 + H2O Ca(CO3) + HCl ----> CaCl2 + H2O + CO2 Zn + CuCl2 ----> ZnCl2 + Cu CuCl2 + Na3(PO4) ---> Cu3(PO4)2 + NaCl HCl + Na(OH) ----> H2O + NaCl C2H6O + O2 -----> CO2 + H2O
Conclusion A summary that includes the following: Identify and explain the types of reactions obsvd. ? Based on the data section explain which reactions were exothermic and endothermic. Which reaction(s) did you like the best and why? What did you learn from this lab? (be specific)