Chem 1211 1st Edition Lecture 7 Outline of Last Lecture I Percent Composition II Formulas from Elemental Composition Outline of Current Lecture I Balancing Equations Current Lecture I Balancing Equations a ConcepTest For this reaction that describes a steelmaking process a Fe 2O3 b C c Fe d CO2 which coefficients represent the balanced equation i Answer a 2 b 3 c 4 d 3 b ConcepTest For the reaction P4 6 Cl2 2 PCl3 in which the product begins to burn what went wrong i Answer Nothing went wrong the reaction occurred and it gave off enough heat to ignite c ConcepTest For this reaction that describes a steelmaking process 2 Fe 2O3 3 C 4 Fe 3 CO2 what percentage of the mass of the products escapes to the atmosphere i Answer 37 ii Reasoning The total mass of the products is 4 x mass of Fe 3 x mass of C 6 x mass of O 355 4g 1 The part of the product that escapes to the atmosphere is 3 CO2 take the total mass of 3 CO2 and divide it by the total mass of the products 2 This gives you 37 multiply by 100 to get the percentage and the answer is 37 d Law of Conservation of Mass i Matter is not created or destroyed ii Balanced chemical equations iii Formulated by Antoine Lavoisier in 1789 e ConcepTest This reaction describes the formation of ammonia 2H2 N2 2 NH3 At equilibrium which of the following are TRUE These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute i Three H2 and one N2 are required to form each NH3 ii Some H2 and N2 still exist as those molecules iii Some NH3 is reverting back to H2 and N2 1 Answer ii and iii this is a equilibrium reaction
View Full Document
Unlocking...