# Chemistry - Chapter 1 2

## Terms

undefined, object
copy deck
unit
fixed standard of measurement
precision
closeness of set of values obtained from identical measurements of a quantity
accuracy
closeness of a single measurement to its true value
significant figures
those digits in a measured number that include all certain digits plus one final one having some uncertainty
number of sig figs
number of digits reported for the value of a measured or calculated quantity; indicating precision of the value
4 rules of sig fig
1. zeros at beg (left of decimal) aren't sig

2. Terminal zeros (right of decimal) are dig

3. Terminal zeros (left of decimal might be sig
Scientific Notation
Representation of number in form A x 10^n
2 rules of sig fig calculation
1. Multiply and divide - answer will have least number of sig figs

2. add subtract -- answer will have least number of decimal places
exact number
number that arises when you count items or when you define a unit
rounding
procedure of dropping nonsig digits in a calculation and adjusting the last digit reported
Rounding rules
1. If digit is 5 or greater drop it and all other to right and add 1 to last digit

2. If digit is less than 5 drop it all digits past it
SI Base Units

length
meter m
mass
kilogram kg
time
second s
temperature
kelvin K
amount of substance
mole mol
electric current
ampere A
Luminous intensity
candela cd
10^18
exa
E
10^15
peta
P
10^12
tera
T
10^9
giga
G
10^6
mega
M
10^3
kilo
k
10^2
hecto
h
10
deka
da
10^-1
deci
d
10^-2
centi
c
10^-3
milli
m
10^-6
micro
u -mu
10^-9
nano
n
10^-12
pico
p
10^-15
femto
f
10^-18
atto
a
Formula to convert K and degrees C
Kelvin equals celcius times 1K over IC and then add 273.15K
Formula to convert C to F
celcius equals 5 deg C over 9 deg F times the result of temp in F minus 32 deg F
SI derived unit
unit dervived by combining base units
area
length squared
m^2
volume
length cubed
m^3
density
d=m/V
speed
distance traveled per unit of time
m/s
acceleration
speed changed per unit of time
m/s^2
force
mass times acceleration of object
kg x m/s^2 (=newton, N)
pressure
force per unit area
kg/(m * s^2) (=pascal, Pa)
Energy
force times distance traveled
kg * m^2/s^2 (=joule, J)

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