1. Problem Solving in Chemistry

2. Skills Used in Problem Solving We are faced with problems each day, and not just in chemistry An answer needs to be found Trial and Error may work sometimes But, there is a method to problem solving that works better, and these are skills that no one is born knowing – they need to be learned. Effective problem solving usually involves two general steps: 1) Developing a plan 2) Implementing that plan

3. Solving Numerical Problems Measurements are an important part of chemistry so many of our word problems involve use of mathematics  Word problems are real life problems, and sometimes more information is presented than needed for a solution Following skills presented will help you become more successful

4. Solving Numerical Problems The three steps we will use for solving a numeric word problem are: 1) Analyze 2) Calculate 3) Evaluate ACE

5. Analyze Determine what are the known factors, and write them down on your paper! Determine what is the unknown. If it is a number, determine the units needed Plan how to relate these factors- choose an equation; use table or graph

6. Calculate If your plan is correct, this is the easiest step. May involve rearranging an equation algebraically; or, doing some conversion of units to some other units.

7. Evaluate Is it reasonable? Make sense? Do an estimate for the answer, and check your calculations. Need to round off the answer? Do you need scientific notation? Do you have the correct units? Did you answer the question ?

8. Sample Problem 1.1 Estimate Walking Time You are visiting Indianapolis. You decide to walk from the Indiana State Capital to the Murat Centre for an afternoon performance. According to the map, the shortest route from the capital to the theater is 8 blocks. How many minutes will the trip take if you can walk 1 mile in 20 minutes? Assume that 10 blocks equals 1 mile. Start Finish

9. Solving Conceptual Problems Not all word problems in chemistry involve doing calculations Nonnumeric problems are called conceptual problems – ask you to apply concepts to a new situation Steps are: 1) Analyze 2) Solve Plan needed to link known to unknown, but no checking units or calculations

10. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. Sample Problem 1.2 Scheduling Classes Manny needs to schedule his classes for next year. The school day is divided into seven periods, and he must take Algebra II, Art, Chemistry, English, History, and Physical Education. Using the information from the course catalog, find a way for Manny to schedule all his classes. Algebra II is offered during either 1st or 2nd period. Algebra II is offered during either 1st or 2nd period. Art is offered during 2nd period only. Art is offered during 2nd period only. Chemistry is offered during either 3rd or 6th period. Chemistry is offered during either 3rd or 6th period. English is offered during either 6th or 7th period. English is offered during either 6th or 7th period. History is offered during either 4th or 7th period. History is offered during either 4th or 7th period. Physical Education is offered during 4th period only. Physical Education is offered during 4th period only. Lunch is scheduled for 5th period. Lunch is scheduled for 5th period.