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Chapter 1
Asking Questions and Solving Problems
- ______- the knowledge obtained by observing natural
events and conditions in order to discover facts
and formulate laws or principles that can be
verified or tested
Branches of Science
1) ______
- Botany
- Zoology
- Ecology
- many others
2) ______
- Physics (forces and energy)
- Chemistry (matter and its changes)
3) ______
- Geology
- Meteorology
- many others
- pure science- continuing search for scientific knowledge
- engineers look for ways to use this
knowledge for practical purposes
- - application of science for practical purposes
Scientific Laws and Theories
-______- a summary of many experimental results
and observations
- describes what happens, not why
- allows for predictions to be made
- Scientific theory( )- explanation of why things work
- based on lots of experiments,
observations, and occurrences
- must be repeatable
- also predict the results of future
experiments
*- often misused
- must explain everything in the
past and future
- replace or change
- always being tested
- laws and theories may be expressed as
1) ______- mathematical equation
2) ______- words/description
Model of Matter
- - used in science to represent an object or event
that can be studied to understand the real object
or event
- may be too large or too small to see; or too
complex
- purpose- provide a description of something
unfamiliar using as familiar objects as
possible
3 Features of Scientific Models
1) simple to ______and ______
2) ______and _____ together different phenomena
3) can ______natural occurrences and the results of future
experiments
***must be able to change to explain ______
______
- helps to find and evaluate possible answers
1) define the ______
2) state the ______
3) perform ______
4) draw ______
-record and analyze ______
5) ______results
Spontaneous Generation
- theory in which something came from nothing
- recipe for rats (grain and cloth in corner later rats appear)
- defining the problem
-ask questions, solving problems can’t begin until a
problem is identified
- suggesting an answer
- hypothesis- ______
- ______experiments
1) observation of nature (______)
2) ______experiments
- variable- any part of an experiment that can
______
* only change ______variable at a time
- ______- info. collected during an
experiment
-recorded observations measurement
*** no experiment is a failure ***
- all help to revise ______
- draw conclusion
- - judgment based on the analysis of data
- will prove or disprove the hypothesis
- critical thinking- the ability and willingness to access
claims ______and to make judgments
on the basis of ______and ______
reasons
Measurement
- - a unit upon which everyone agrees
- SI- International system of units
- everyone can communicate ______easier
** prefixes are multiples of 10**
deci d tenth 10-1
centi c hundredth 10-2
milli m thousandth 10-3
micro mu millionth 10-6
nano n billionth 10-9
kilo k thousand 103
mega M million 106
giga G billion 109
- ______- meter stick, ruler, tape measurer
- standard unit—______
- ______- space that an object takes up
- standard unit—______
- liquids—use a graduated cylinder
- read at eye- level and at the meniscus
- ______- bottom of the curve of the liquid
- usually use mL (milliliter)
- Solids
- use the cm3; 1cm3 = 1mL
- regular solid
-measure 1 x w x h= volume
- irregular solid
- ______
- read level of water
- add solid
- reread the level
-______- the amount of matter in an object
- use a balance
- standard unit; ______
- usually use – gram
- 1 gram = 1 paperclip
- mass vs. weight
- mass is constant
- weight depends on ______
- temperature- thermometer
- standard unit – ______
-use Celsius more often
0C + 273 = Kelvin
0 Kelvin – ______(-273 oC)
______
Area and Density
- quantities that cannot be measured directly
- they require a formula of some sort
- area- how much space an object takes up
Ex. square l x w
4 cm x 4 cm
16cm2
- density- ratio of mass to volume
d = m units: g or g
v cm3 mL
(solid) (liquid)
Graphing
3 common types
1) ______
- best for displaying data that change
- - chosen by researcher (x-axis)
- - value depends on what happens in
the experiment (y-axis)
2) ______
- best when you want to ______similar data for several
individual items or events
- clearly shows how large or small the ______in
individual values are
3) ______
- good for displaying data that are parts of a whole
Scientific Notation
- used to express very large or very small numbers
- Ex.- speed of light is 300,000,000 m/s
3 x 10 8 m/s
- reduces the number of ______
- basically it is a number times a power of ______
104 = 10,000
103 = 1,000
101 = 10
10-1 = .1
10-3 = .001
- when using scientific notation in a calculation follow
these rules
1) LEARN TO USE YOUR CALCULATOR!!!
“___” or “___” keys are the same as x10
- EX.- 5 x 103 in calc. is 5 “EE” or “EXP” 3
or
1) when ______two values
- add the powers of 10
2) when ______two values
- subtract the powers of 10
Significant Figures
- a prescribed decimal place that determines the amount of
______to be done on the precision of the
measurement
Accuracy vs. Precision
- - how close the measured value is to the real
value
- - exactness of a measurement
-limited by the smallest division on the scale of
the measuring device
- accuracy- how good you did measuring
- precision- how accurate the tool is
- an answer can only be as precise as the ______precise
measurement
- least precise measurement is the one with the fewest
______
Significant figures rules:
1) ______in a number are not always significant
- Ex.: .00005 or 5000 compared to .0053020 or 5002
2) addition and subtraction rule is that the answer should
have the same number of ______to the _____ of the
decimal
- Ex.: 3.84 + 27.1
- add with a calculator
- answer reads 30.94 (incorrect)
- should be 30.9
3) multiplication and division rule is the final answer has
the same number of significant figures as the
measurements having the ______number of significant
figures
- Ex. 5.871 m x 8.14 m
- multiply with a calculator
- answer reads 47.78994 m2 (incorrect)
- should be 47.8 m2