1. Chapter 1 “Introduction to Chemistry”

2. What is Chemistry?
Chemistry is the study of the composition of “matter” – (matter is anything with mass and occupies space), its composition, properties, and the changes it undergoes.
Has a definite affect on everyday life - taste of foods, grades of gasoline, etc.
Living and nonliving things are made of matter.

3. Chemistry is the study of the composition, structure, and properties of matter and the changes it undergoes – such as burning fuels.
C2H5OH O2  2 CO2 + 3 H2O + Energy
Reactants  Products

4. 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 not firm – they overlap and interact

5. - Page 8

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

7. Why Study Chemistry?
Everyone and everything around us involves chemistry – explains our world
What in the world isn’t Chemistry?
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?

8. Chemistry Far and Wide
Chemists design materials to fit specific needs – velcro (Patented in 1955) on page 12
perfume, steel, ceramics, plastics, rubber, paints, nonstick cooking utensils, polyester fibers
Two different ways to look at the world: macroscopic and microscopic

9. 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!)

10. 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

11. 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

12. 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

13. - 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.

14. 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?

15. 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

16. 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

17. Oxygen was required! 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!

18. The Scientific Method
The process researchers use to carry out their investigations. It is a logical approach to solving problems.
Starts with observation

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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

20. 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

21. 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

22. 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

23. 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

24. 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.

25. 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?
Is the Internet reliable information?

26. Problem Solving in Chemistry
We are faced with problems 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, and these are skills that no one is born knowing – they need to be learned.

27. 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.

28. Solving Numeric Problems
Measurements are an important part of chemistry; thus many of our word problems involve use of mathmatics
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

29. 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!

30. Solving Numeric Problems
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

31. Solving Numeric Problems
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.

32. Solving Numeric Problems
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?

33. 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:
Analyze and 2) Solve
Plan needed to link known to unknown, but no checking units or calculations
Do Conceptual Problem 2.1 on page 46

34. Introduction to Chemistry
End of Chapter 1
Introduction to Chemistry