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THE NATURE OF SCIENCE
INTEGRATED SCIENCE
MS. WACK
In this section you will learn the basics of scientific investigations, including the scientific method, graphing, modeling, measuring
and properly reporting your measurements .
Branches of Science
Earth Science: The scientific study of the planet Earth
Life Science: Any science that deals with
living organisms, their life processes, and
their interrelationships.
Branches of Science
Branches of Science
Physical Sciences
1) Chemistry: The study of matter and energy
2) Physics: The study of the interactions between matter and energy
SCIENTIFIC MODELS
Model: An idea, system or mathematical
expression that is similar to the idea being
explained
Model of an Atom Model of a Cell Model of Earth’s Layers
Accuracy
• An accurate measurement is one that is the desired value or is very close to the desired value
• Accuracy: Measurements are close to the actual value
Precision
• Precise measurements are measurements that are close to each other (getting the same measurements every time)
• Precision: Reproducibility or Repeatibility
What is the difference between precision & accuracy?
Precise measurements do not have to be accurate,
but accurate measurements are
always precise!
SCIENTIFIC NOTATION
• A number is written in 2 parts.– The first part is a number
between 1 & 10– The second part is a
power of ten
• Exponent– Positive exponents
represent numbers greater than 1
– Negative exponents represent numbers less than 1
Scientific Notation• To convert a number to scientific
notation:– Count how many places the decimal place
must be moved to make the number a number between 1 & 10 (the coefficient)• The number of spaces the decimal moved is
the value of the exponent– If you moved the decimal to the right, the
exponent is negative– If you moved the decimal to the left, the
exponent is positive– Write: Coefficient x 10exponent
SCIENTIFIC NOTATION
• To convert a number from scientific notation to regular notation:– If the exponent is positive, move the decimal in
the coefficient the number of spaces indicated by the exponent to the right
– If the exponent is negative, move the decimal in the coefficient the number of spaces indicated by the exponent to the left.
SCIENTIFIC NOTATION PRACTICE PROBLEMS
Express the following measurements in scientific notation.453.32________________ 1000_____________________0.0000421_____________ 0.00040___________________
Convert the following to standard notation3.0 x 106______________ 4.4 x 10-7__________________1.49 x 10-5_____________ 3.75 x 102_________________
Perform the following using scientific notation.(9.39x106)x(4.37x10-8) =____________________________(5.12x103)(8.61x104)=____________________________
What do the countries in red have in common?
International System of Units (SI Units)
• A revised version of the metric system that was developed in France in 1795 and was adopted by international agreement in 1960
• There are 7 base SI units– All other SI Units are DERIVED from the 7
base units
Base Units: The 7 metric units that SI is built upon
Physical Quantity
Unit Name Unit Symbol
Measured using…
Mass
Length
Time
Quantity
Temperature
Electric Current Ammeter
Luminous Intensity
Photometer
NON-SI UNITS
Physical Quantity Unit Name Unit Symbol
Volume
Pressure
Temperature
Energy
Derived Units Commonly Used in Chemistry
Physical Quantity
How to Calculate
Unit Name Unit Symbol
Volume
Area
Density
To Derive a Unit• Write the mathematical formula for the quantity.• Replace the formula with units and simplify.
Practice Problems
• Calculate the area of a space having a length of 3.2 cm and a width of 2.1 cm.
• A cube measures 0.02 cm on each side. What is the volume of this cube?
• What is the density of the cube above if its mass is 1 g?
Common US-Metric Conversions
METRIC CONVERSIONS
DIMENSIONAL ANALYSIS
Dimensional analysis is a method used to convert between units
•Uses units that are equal to each other in ratio form to convert between units
2300 seconds x 1 minute x 1 hour x 1 day = .02 days
60 seconds 60 minutes 24 hours
METRIC PREFIXES
METRIC PREFIXESPREFIX In 1 base unit there
are:Example
mega- (M) 10-6 M-unit 1 m = 10-6 Mm
kilo- (k) 10-3 k-unit 1 L = 10-3 kL
deka- (dk) 0.1 dk-unit 1 g = 0.1 dkg
BASE UNIT
deci- (d) 10 d-unit 1 s = 10 ds
centi- (c) 100 c-unit 1 mol = 100 cmol
milli- (m) 1000 m-unit 1 m = 1000 mm
micro- () 106 -unit 1 L = 106 L
nano- (n) 109 n-unit 1 g = 109 ng
pico- (p) 1012 p-unit 1 s = 1012 ps
Steps to Dimensional Analysis1. Start with what you know
(number and unit).2. Times a line.3. Add a conversion factor so that
units cancel and what you are looking for is on top of the ratio.
4. Check your answer.
DIMENSIONAL ANALYSIS
1 Base Unit Equals
10-6 Mega-10-3 kilo-0.1 deka-10 deci-
100 centi-1000 milli-106 micro-109 nano-1012 pico-