Summary Chemistry and the Scientific Method

Chapter / { Chemistry and the Scientific Method .


Coulombs Law - The force between charged particles can be used What is measured , → Unit of measurement → Symbol
to explain the properties of matter down -109 subatomic level
Length → meter → m
Scientific Method -




Kilogram Kg
" → →
Use of
carefully controlled experiments -10 answer scientific questions ? MASS
1. Question ?
2. collect information '
/ Data temperature → Kelvin →
K
3. Hypothesis
4. Perform Experiments
5. Pattern / constant relationship ? TIME → Second →
g
Qualitative Data -
amount of substance
→ mole → MOI
" "


Consisting of descriptive observations .




Metric system -




Quantitative Data -


Preferred system of units
" used in scientific work .
"




" "

Consisting of numbers obtained by measurement .




51 Units -



''
in terms of just one set of metric units
express all measurements
" .




Hypothesis
. .-



-




Volume -
amount of space occupied by
a substance

An idea or theory that is not proven
but that leads -10 further
study or discussion
unit of volume, one cubic declmetre ( 0.001 cubic metre)
liter
-
-




Law of nature or scientific law theory -




"
After many experiments , a pattern may emerge in the form of a constant relationship among millimeter -
mill molar; IMM -
_ 10-3114--10-314=10 3m01 / L -




"
Phenomena under the same conditions .




volume ofacube that measures lcmxlcmxlcm
cubic centimeter
-




Theory -




unit of mass
kilogram Kg; basic
" -

explains the law based on the experimental observations
unifying principle that
" .

. . _
a ,




Quantitative Measurement - grams
-
g ; basic unit of mass

"
of matter within a sample
"
Measurements in which the result is expressed as a number .


mass -

property that reflects the quantity


absolute temperature scale ; zero at absolute
Qualitative Observation Kelvin temperature scale
- zero
-




"
chemical
Note general characteristics , such as color, odor > taste, and the tendency to undergo scale -51 temperature scale
change in the presence of other substances .
"
Celsius temperature

Law of Conservation of mass
-
Density -
massofaunit volume ofamaterial substance
;d=rg
equal -10 the total mass of the
"
In a chemical reaction > the total mass of the reacting substances is
"
conserved chemical reactions
Products formed In other words
.
. . _
mass is in
.




Scientific Notation -




"
of 10
The expression Ofa number multiplied by the power
" .




Prefix →
Symbol →
Multiple → Example
g. Iga
-
→ f- → 109 or 1000000000 → / gigajoule ,
/ GJ -1×10-
"
Joules


→ M → 106 or 1000000 → /
megajoules 1145=1×106 Joules
mega
- ,




14110 - → K → 103 or 1000 → / Kilometer , 1km =/ ✗ 103 meters



Zor → / Centimeter / cm -1×10-2
"
1100
-

meters
→ 10
-




cent, -
→ C ,




10-3 Or 1/1000 → / millimeter , / mL -1×10-3 Liters
→
-




Milli -
→ m


→ 10
-
◦
or 1/1000000 → / microsecond /
,
145=1×10-6 seconds
micro -
→ µ
_
"

nano -
→ n → 10-9 or 1/1000000000 → / nanometer , / nm -1×10 -
meters




PICO → P 10-12 or / 1000000000000 → lpicometer 1pm : 1×10-12 meters
-

→ I ,




f- em-10 → f- 10-15 or femtosecond Ifs -1×10-15seconds
/ 1000000000000000 → 1
-
1,
→
-
,




a /⑤
Atto → latta-soule.la-0=1×10-18 Joules
→
1/1000000000000000000
-
-



→ 10 op