Chapter 11 Chemical Reactions Activities and resources •Writing Chemical equations Lab –chemical reactions •Balancing Equations Workshops •Classifying reactions TB & Workbooks •Predicting the products Animations and games for balancing equations and types of reactions: •Reactions in aqueous solutions (complete and net ionic equations) •Predicting the formation of a precipitate http://funbasedlearning.com/che mistry/chemBalancer/ques5.htm http://www.youtube.com/watch?v=iHHvx1VC_8&NR=1 http://www.youtube.com/watch?v=tE 4668aarck&feature=related 11.1 Describing Chemical Reactions > Writing Chemical Equations Word Equations To write a word equation, write the names of the reactants to the left of the arrow separated by plus signs; write the names of the products to the right of the arrow, also separated by plus signs. Reactant + Reactant Product + Product Slide 2 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Describing Chemical Reactions > Writing Chemical Equations Methane + Oxygen Carbon dioxide + Water (the reaction between methane and oxygen can be described as a combustion reaction.) Slide 3 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Describing Chemical Reactions > Writing Chemical Equations iron + oxygen iron(III) oxide (the reaction between Fe and O2 to form Fe2O3 can be described as a combination or synthesis reaction) Slide 4 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Describing Chemical Reactions > Writing Chemical Equations Chemical Equations A chemical equation is a representation of a chemical reaction; the formulas of the reactants (on the left) are connected by an arrow with the formulas of the products (on the right). Slide 5 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Describing Chemical Reactions > Writing Chemical Equations Slide 6 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Describing Chemical Reactions > Writing Chemical Equations A skeleton equation is a chemical equation that does not indicate the relative amounts of the reactants and products. (i.e. the equation is not yet balanced) Here is the equation for rusting: Fe + O2 Fe2O3 How would you balance this equation? Slide 7 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Describing Chemical Reactions > Writing Chemical Equations A catalyst is a substance that speeds up the reaction but is not used up in the reaction. Without Catalyst With Catalyst Slide 8 of 37 © Copyright Pearson Prentice Hall End Show Slide 9 of 37 © Copyright Pearson Prentice Hall End Show Slide 10 of 37 © Copyright Pearson Prentice Hall End Show Slide 11 of 37 © Copyright Pearson Prentice Hall End Show Practice Problems for Conceptual Problem 11.1 Slide 12 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Describing Chemical Reactions > Balancing Chemical Equations Balancing Chemical Equations What are the steps in writing a balanced chemical equation? To write a balanced chemical equation, first write the skeleton equation. Then use coefficients to balance the equation so that it obeys the law of conservation Slide of mass. 13 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Describing Chemical Reactions > Balancing Chemical Equations A chemical reaction is also described by a balanced equation in which each side of the equation has the same number of atoms of each element and mass is conserved. Slide 14 of 37 © Copyright Pearson Prentice Hall End Show Slide 15 of 37 © Copyright Pearson Prentice Hall End Show Slide 16 of 37 © Copyright Pearson Prentice Hall End Show Slide 17 of 37 © Copyright Pearson Prentice Hall End Show Slide 18 of 37 © Copyright Pearson Prentice Hall End Show Go to following website for balancing chemical equation game: http://funbasedlearning.com/chemistry/chemBalancer/ques5.htm Complete worksheet (class handout) and turn in for grading Slide 19 of 37 © Copyright Pearson Prentice Hall End Show Practice Problems for Conceptual Problem 11.2 Slide 20 of 37 © Copyright Pearson Prentice Hall End Show Slide 21 of 37 © Copyright Pearson Prentice Hall End Show Slide 22 of 37 © Copyright Pearson Prentice Hall End Show Slide 23 of 37 © Copyright Pearson Prentice Hall End Show Slide 24 of 37 © Copyright Pearson Prentice Hall End Show Practice Problems for Conceptual Problem 11.2 Slide 25 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Section Quiz. Assess students’ understanding of the concepts in Section 11.1. Continue to: -or- Launch: Section Quiz Slide 26 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Section Quiz. 1. Propane gas reacts with oxygen to produce water vapor and carbon dioxide. Choose the correct word equation for this reaction. a. propane + carbon dioxide water + oxygen b. propane + oxygen + water carbon dioxide c. propane + oxygen + water + carbon dioxide d. propane + oxygen water + carbon dioxide Slide 27 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Section Quiz. 2. Which of the following is a skeleton equation? a. H2 + CO CH3OH b. 2H2 + CO CH3OH c. 2H2 + CO2 CH3OH d. hydrogen + carbon monoxide methanol Slide 28 of 37 © Copyright Pearson Prentice Hall End Show 11.1 Section Quiz. 3. What coefficient for H2SO4 is required to balance the following equation? Ca3(PO4)2 + ____ H2SO4 3CaSO4 + 2H3PO4 a. 1 b. 2 c. 3 d. 4 Slide 29 of 37 © Copyright Pearson Prentice Hall End Show