1. General Chemistry CHEM 1103 Summer, 2003
Nicholas H. Snow
Department of Chemistry and Biochemistry
Seton Hall University
Dr. W. R. Murphy, SHU

2. Course Structure MTR meetings 0815-1110 MTR Meetings 1130-1430
lectures
Discussion/problems
Quizzes (0815 Thursdays)
MTR Meetings
Laboratory
Laboratory meets in McNulty 321

3. Course Structure, con’t
CHEM 1107
Course Structure, con’t
Four quizzes points each
short answer, long answer
Laboratory points
Final points
final will be multiple choice first semester ACS examination
Dr. W. R. Murphy, SHU

4. Study recommendations
Study chemistry a few hours everyday; cramming does not work!
Study ahead, so that you know what is coming
Ask Matt, Rafael and me questions!
You should not have to study for the tests if you have properly prepared

5. Chapter 1 - What is Chemistry?
Science is the attempt to organize and study nature
Chemists are interested in all matter
Includes problems in material science and biochemistry
micro- and nanoelectronics
medicine
green chemistry
In particular
properties of matter
transformations of matter
interactions of different types of matter

6. Experimentation How we learn about matter and nature
Chemistry can advance by:
deliberately planned courses of experimentation
accidental discoveries
Our experimentation and interpretation must be designed to be prepared for both possibilities
Experimentation can also be driven by improvements in methodology and technology (better equipment and methods)

7. Scientific method Hypothesis - initial idea about what matter will do
Experiment - test of the hypothesis
Theory - an explanation of what was observed
Laws - statements summarizing observations (not explanations)

8. Structure of matter Properties of matter Composition of matter
macroscopic (can be seen with the eye)
microscopic (underlying structure)
Composition of matter
atoms - basic unit of matter
molecules - combinations of atoms
There are a little over 100 types of atoms, but only about 20 are commonly encountered

9. Chemicals Elements - types of atoms
Compounds - substances composed of two or more different atoms in a definite proportion by mass
Chemical formulas
indicate the atoms in the compound
number of each atom in the compound is designated by subscripts

10. Periodic Table
Elements demonstrated properties that repeated in a cyclical or periodic fashion
Properties included both physical and chemical
Gross organization of periodic table
metals
metalloids
nonmetals

11. Periodic Table Metals Nonmetals Metalloids
good conductors of heat, electricity
shiny, malleable, ductile
all solids except Hg
Nonmetals
properties are highly variable, but are generally poor conductors
can be brittle solids, gases or liquids
Metalloids
often called semiconductors
dull, brittle solids

12. Families Rows are called periods Columns are called families
alkali metals
alkaline earths
noble gases
halogens
chalcogens
pnicnogens

13. Characteristics of matter
Elements - matter that cannot be broken down into simpler substances by chemical means
Compounds - combinations of two or more different elements in definite proportion by mass
Mixtures - combinations of matter that can be separated by physical means

14. Phases of matter
gas - particles of matter not in constant contact and are constantly moving
does not have a specific shape
does not have a specific volume
liquid - particles are in constant contact, but are still in constant motion
has a specific volume
does not a definite shape
Solid - particles are in contact and cannot move through the material
has a specific volume and shape

15. Mixtures
homogenous - same throughout down to the molecular level; often called a solution
heterogeneous - contains regions or phases of different matter; especially at the macroscopic level

16. Physical properties can be measured without changing the substance
those typically measured
volume
mass
time
temperature

17. Measurement
Scientific notation (do you know how to use your calculator?)
Units
prefixes (memorize them)
SI and common metric units
Dimensional analysis
Precision - exactness of a measurement
Accuracy - how close a measurement is to the “true” value

18. Significant Figures number of digits expressed in a numerical value
all nonzero digits are significant
imbedded zeroes are significant
zeroes used to hold place are generally not significant
12,000 - hard to say
zeroes here are not significant

19. Calculations
Physical properties are often measured that must be incorporated in calculations to yield chemically significant information
Density is a good example:

20. Properties
Extensive properties are those that depend on the amount of a substance
mass and volume
Intensive properties depend on the material and are independent of the amount of material
density is a good example

21. Precision in calculations
Scientific measurements often require several measurements from more than one instruments
This data is then used to calculate a quantity of interest
For example, to measure density, one must measure mass and volume using two separate instruments

22. Precision of calculations
When adding or subtracting, the number of decimal places in the result is the number of decimal places in the number with the fewest places
When multiplying or dividing, the number of significant figures in the result is the same as in the quantity with the fewest significant figures
Postpone adjusting the result to the correct number of significant figures until the calculation is complete
Remember, the calculator always gives you too many significant figures.