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Chapter 1 Notes
*Chemistry is the study of the composition, structure, and properties of matter and the changes it undergoes.

Applied science / Technology
Branches of Chemistry
Chemical is not an ugly word.
Matter and its properties

Matter

    Volume
    Mass

Atom

Element

Compound


*Physical Properties; characteristic that can be observed or measured without changing in the identity of a substance.
Ex: Grinding, melting, cutting, boiling, malleability, and conductivity.


States of matter
Solid : definite shape and volume
Liquid : definite volume indefinite shape
Gas : indefinite shape and volume
          Plasma
Entropy

Chemical properties: A substance's ability to undergo changes that transform it into a different substance.
Ex: Burning, digesting, rusting (oxidation), tarnishing

Chemical Change: a change in which one or more substances are converted into different substances.
Indications of chemical change: Precipitate, evolution of gas, color change and /or energy change sometimes color.

Endothermic : Energy is absorbed from the environment
Exothermic : Energy is released to its environment

Chemical reactions:  Chemical Changes
Reactants      ®     Products

Ex:  Hydrogen plus Oxygen makes water


H2  +  O2   =  H2O


Classification of matter (transp.)



Intro. periodic table

Groups / Families vertical columns ...Elements are similar in chemical and physical properties.

Periods rows from left to right....elements with changing chemical and physical properties however are more similar to the ones closest to it.

Types of elements
Metals
    Characteristics
        Ductile
        High tensile strength
        Malleable
        high m.p
        High tensile strength.
Unique metals
Hg - liquid
Al - soft
Mg & Bi - brittle
Cu - reddish brown solid
        Green to blue when bonded to S and O
Nonmetal: An element that is a poor conductor of heat and electricity
brittle, low melting point, dull

Metalloids: An element that has some characteristics of metals and some characteristics of nonmetals
Noble Gases group 18 or 8 relatively unreactive

Cha 2 Chemistry notes
Sci. Measurement
Qualitative:  Subjective nonnumeric
Quantitative:  Objective numerical
International System: Revised Version of the metric system
Units= define the numbers
Measurements contain two parts 1) number 2) unit
Ex:  2ml

Standards: Agreed upon unit of comparison
Metric system is the system adopted for its 1) convenience based on ten
2) Simple conversion
SI Base units
Length meter          m
Mass Kilogram Kg
Time Second s
Thermodynamics temp. Kelvin K
Amount of a substance mole mol
Luminous Intensity candela cd

Length: Measures distance
Instrument: Meter stick
Simple conversion:  

Volume: The amount of space matter takes up
Unit: Derived from the SI unit for length
Ex: Regular shaped objects
    V = L x W x H
Ex:
         Liter is the volume of a cube that is 10 cm high, 10 cm long, and 10 cm wide.
Ex:  Irregular shape objects: water displacement

1 L = 1 dm3 = 1000 cm3 = 1000 ml

VII.      Mass vs. weight
Mass is the amount of matter an object contains
Weight is the amount of gravitational pull on an object.

Mass
Standard 1 Kg
Tool- Balance/scale

VIII.    Density: Amount of mater per unit volume. (Derived unit)
Density of water = 1 g/cm3
Ex:

IX.       Specific gravity: Ratio between the density of a substance and the density of water.


Specific gravity =         Density of substance
            ___________________
                Density of water
Ex:

         water is used as the standard for liquids
         H gas or air is used as a standard for gases
Temperature: The degree of hotness or coldness of an object
Heat flows from an area of [high ] to an area of [low].
[   ] = Concentration

X.      Metric system uses o C   f.p. water = 0oC
                b.p. water = 100oC

Metric System and Scientific Notation

Metric System
Metric Units
The basic units of measure in the Metric System are:
Length Meter (m)
Capacity (liquid measure) Liter (l)
Weight Gram (g)
Pressure Bar (b)
Temperature Celsius (°C), Kelvin (K)
Force Newton

Multiples of the basic units are designated by the following prefix: (the "c" is pronounced like a "k")
deka- 10 Example: dekagram 10 grams
hecto- 100 Example: hectoliter 100 liters
kilo- 1000 Example: kilometer 1000 meters
Fractions of the basic units are designated by the following prefix: (the "c" is pronounced like an "s")
deci- 0.1 Example: decimeter 0.1 meters
centi- 0.01 Example: centigram 0.01 grams
milli- 0.001 Example: millibar 0.001 bars
Metric System Conversions
Changing metric units is as simple as multiplying or dividing by 10 or 1000. The diagram below shows you how to convert one unit into another by a series of multiplication or division.

km - kilometer m - meter dm - decimeter cm - centimeter mm - millimeter
Convert the following values. (enter all values without commas - example 5,678 would be entered as 5678)
1. 7 cm = mm
2. 3,450 mm = cm
3. 45 m = cm
4. 10,946 m = km
5. 18,300 cm = m
6. 75.3 km = m
7. 63.9 cm = mm
8. 4 m = cm
9. 63 km = m
10. 19 km = mm
17. 1 kilometer = meter
18. 1 meter = decimeters
19. 1 meter = centimeters
20. 1 meter = millimeters
21. 1 centimeter = millimeters
22. 1 km = millimeters
Scientific Notation
The mass of the Earth is 5,979,000,000,000,000,000,000,000,000 kilograms. The molecular diameter of ammonia is 0.0000000297 centimeters. Very large and very small numbers are prone to errors when writing these numbers or typing them. To prevent these types of errors, these numbers can be written in a form called scientific notation. This allows numbers to be written as the product of a power of 10 and a number greater than or equal to 1, but less than 10. The mass of the Earth in scientific notation is 5.979 x 1027 kg and the molecular diameter of ammonia is 2.97 x 10-8 cm.
The simplest method for conversion of standard notation to scientific notation is move the decimal. For very large numbers, move the decimal to the left, until it is after the first numeral. Count the number of places the decimal has moved. This then becomes the exponent on the 10.

   7,456,000,000 =
   384,400 =
   7423 =
   543,332,000,000,000,000,000 =
   0.000032 =
   0. 0.065 =
   0.000000000000000000000062 =
   Write the following using standard notation. (enter all values without commas - example 5,678 would be entered as 5678)(enter all decimal values less than
   6.482 x 104 =
   1.42 x 10-8 =
   4.85 x 1012 =
   3.4 x 10-3 =
   2.76 x 1016 =
   8.6 x 10-17 =
   6.26 x 101 =
Scientific notation and calculator
Entering scientific notation into a calculator is accomplished in various manners, depending on the type of calculator you are using. A common method uses the EE key. Check your calculator manual for detailed directions if the EE key is not present or ask the instructor for help.
EXAMPLE
To enter the number 7.42 x 1022, begin by entering 7.42. Then press the EE key. Then enter 22. You may then proceed with normal calculations.
EXAMPLE
To enter the number 3.64 x 10-13, begin by entering 3.64. Then press the EE key, then press the (+/-) key. Then enter 13. NOTE: The (+/-) key is not the same as the (-) function key. The (+/-) key changes the value from positive to negative, while the (-) function key performs subtraction.
Perform the indicated operations. Express all answers in scientific notation.
Use the "E" format for "x10": example 3.46 E -24 (round all decimals to 2 decimal places)(the space before and after the E is important)


   47. (3 x 104)(6.3 x 105) =
   48. (7 x 10-3)(6.1 x 10-8) =
   49. (4.4 x 105)/(9.6 x 1012) =
   50. (7.3 x 104)/(2.8 x 10-7) =

XI.       S. I. System temperature conversion
Kelvin     f.p. water 273 K
        b.p. water 373 K
Absolute zero:  no molecular movement at all

K = oC + 273

Percent error = (accepted - actual)  x  100
                  Accepted