1. Chapter 1 “Introduction to Chemistry”
Pequannock Township High School
Chemistry
Mrs. Munoz

2. Section 1.1 Chemistry OBJECTIVES:
Identify five traditional areas of study in chemistry.
Relate pure chemistry to applied chemistry.
Identify reasons to study chemistry.

3. What is Chemistry?
Chemistry is the study of the composition of “matter”
Has a definite affect on everyday life - taste of foods, grades of gasoline, etc.
Living and nonliving things are made of matter.

4. Chemistry is the study of the composition, structure, and properties of matter and the changes it undergoes – such as burning fuels.
The chemistry is shown as a chemical equation (reaction equation):
C2H5OH O2  2 CO2 + 3 H2O + Energy
Reactants  Products

5. 5 Major Areas of Chemistry
Analytical Chemistry: concerned with the composition of substances
Inorganic Chemistry: primarily deals with substances without carbon
Organic Chemistry: essentially all substances containing carbon
Biochemistry: Chemistry of living things
Physical Chemistry: describes the behavior of chemicals (ex. stretching); involves lots of math!
Boundaries of the areas of chemistry overlap and interact.

6. - Page 8

7. What is Chemistry?
Pure chemistry: gathers knowledge for the sake of knowledge
Applied Chemistry: uses chemistry to attain certain goals, in fields like medicine, agriculture, and manufacturing. Applied chemistry leads to an application
* Nylon – Figure 1.3, page 9
* Aspirin (C9H8O4) - to relieve pain

8. Why Study Chemistry?
Everyone and everything around us involves chemistry – explains our world
Helps you make choices
Helps make you a better informed citizen
A possible career for your future
Used to attain a specific goal
(What did we describe as “pure” and “applied” chemistry?)

9. Section 1.2 Chemistry Far and Wide
OBJECTIVES:
Identify some areas of research affected by chemistry.
Describe some examples of research in chemistry.
Distinguish between macroscopic and microscopic views.

10. Chemistry Far and Wide
Chemists design materials to fit specific needs – velcro (page 12)
Examples of chemistry: perfume, steel, ceramics, plastics, rubber, paints, nonstick cooking utensils, polyester fibers
Two different ways to look at the world: macroscopic and microscopic

11. Energy – we constantly have greater demands
Chemistry Far and Wide
Energy – we constantly have greater demands
We can conserve it; use wisely
We can try to produce more; oil from soybeans to make biodiesel
fossil fuels, solar, batteries (that store energy – rechargeable?), nuclear (don’t forget pollution!)

12. Medicine and Biotechnology-
Chemistry Far and Wide
Medicine and Biotechnology-
Supply materials doctors use to treat patients
vitamin C, penicillin, aspirin (C9H8O4)
materials for artery transplants and hipbones
bacteria producing insulin

13. Chemistry Far and Wide Agriculture Produce the world’s food supply
Use chemistry for better productivity – soil, water, weeds
plant growth hormones
ways to protect crops; insecticides
disease resistant plants

14. Chemistry Far and Wide The Environment
both risks and benefits involved in discoveries
Pollutants need to be 1) identified and 2) prevented
Lead paint was prohibited in 1978; Leaded gasoline? Drinking water?
carbon dioxide, ozone, global warming

15. - Page 16
Let’s examine some information from a graph.
88.2%
440,000
After lead was banned in gasoline and public water supply systems, less lead entered the environment.

16. composition of the planets analyze moon rocks planet atmospheres
Chemistry Far and Wide
The Universe
Need to gather data from afar, and analyze matter brought back to Earth
composition of the planets
analyze moon rocks
planet atmospheres
life on other planets?

17. Section 1.3 Thinking Like a Scientist
OBJECTIVES:
Describe how Lavoisier transformed chemistry.
Identify three steps in the scientific method.
Explain why collaboration and communication are important in science.

18. Alchemy – developed the tools and techniques for working with chemicals
The word chemistry comes from alchemy – practiced in China and India since 400 B.C.
Alchemy has two sides:
Practical: techniques for working with metals, glass, dyes, etc.
Mystical: concepts like perfection – gold was a perfect metal

19. An Experimental Approach
In the 1500s, a shift started from alchemy to science – King Charles II was a supporter of the sciences
“Royal Society of London for the Promotion of Natural Knowledge”
Encouraged scientists to use more experimental evidence, and not philosophical debates

20. Lavoisier
In the late 1700s, Antoine Lavoisier helped transform chemistry from a science of observation to the science of measurement – still used today
He settled a long-standing debate about burning, which was…
Oxygen was required!

21. The Scientific Method
A logical approach to solving problems or answering questions.
Starts with observation- noting and recording information and facts.
hypothesis- a proposed explanation for the observation; must be tested by an experiment.

22. Steps in the Scientific Method
1. Observations (uses your senses) a) quantitative involves numbers = 95oF b) qualitative is word description = hot 2. Formulating hypotheses (ideas) - possible explanation for the observation, or “educated” guess 3. Performing experiments (the test) - gathers new information to help decide whether the hypothesis is valid

23. Scientific Method
“controlled” experiment- designed to test the hypothesis
only two possible answers:
hypothesis is right
hypothesis is wrong
We gather data and observations by doing the experiment
Modify hypothesis - repeat the cycle

24. Scientific Method
We deal with variables, or factors that can change. Two types:
1) Manipulated variable (or independent variable) is the one that we change
2) Responding variable (or dependent variable) is the one observed during the experiment
For results to be accepted, the experiment needs to always produce the same result

25. Outcomes over the long term…
Theory (Model)
- A set of well-tested hypotheses that give an overall explanation of some natural phenomenon – not able to be proved
Natural Law (or Scientific Law)
- The same observation applies to many
different systems; summarizes results
- an example would be:
the Law of Conservation of Mass

26. Law vs. Theory
A law summarizes what has happened.
A theory (model) is an attempt to explain why it happened – this changes as new information is gathered.

27. - Page 22
Using your senses to obtain information
The procedure that is used to test the hypothesis
Hypothesis is a proposed explanation; should be based on previous knowledge; an “educated” guess
Tells what happened
A well-tested explanation for the observations; cannot be proven due to new discoveries

28. Collaboration / Communication
When scientists share ideas by collaboration and communication, they increase the likelihood of a successful outcome
Collaboration – Fig. 1.21, p. 24
How is communication done?

29. Section 1.4 Problem Solving in Chemistry
OBJECTIVES:
Identify two general steps in problem solving.
Describe three steps for solving numeric problems.
Describe two steps for solving conceptual problems.

30. Problem Solving in Chemistry
Problems exist each day, and not just in chemistry.
A solution (answer) needs to be found.
Trial and Error may work… sometimes?
But, there is a method to problem solving that works better. Problem solving skills need to be learned.

31. Problem Solving in Chemistry
Effective problem solving usually involves two general steps:
Developing a plan
Implementing that plan
The skills you use to solve a word problem in chemistry are NOT different from those techniques used in shopping, cooking, or planning a party.

32. Solving Numeric Problems
Measurements are an important part of chemistry. Many chemistry word problems involve use of mathematics.
Word problems are real life problems, and sometimes more information is presented than needed for a solution.
The following skills presented will help you become more successful.

33. Solving Numeric Problems
The three steps we will use for solving a numeric word problem are:
Analyze
Calculate
Evaluate
The following slides tell the meaning of these three steps in detail.
Let’s learn how to ACE these numeric word problems!

34. Solving Numeric Problems, Step 1
Analyze: this is the starting point
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
This is the heart of successful problem
solving techniques – it is the PLAN!

35. Solving Numeric Problems, Step 2
Calculate: perform the mathematics
If your plan is correct, this is the easiest step.
Calculator used? Do it correctly!
May involve rearranging an equation algebraically; or doing some conversion of units to some other units.

36. Solving Numeric Problems, Step 3
Evaluate: – the finishing step
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?

37. Solving Conceptual Problems
Not all word problems in chemistry involve numerical/definitive calculations
Nonnumeric problems are called conceptual problems – just apply concepts to a new situation
Steps are:
Analyze
Solve
Plan needed to link known to unknown, but no checking units or calculations

38. Introduction to Chemistry
Conclusion of Chapter 1
Introduction to Chemistry