Definitions Flashcards
Kelvin
K= c*+ 273
That means that when kelvin is at 273 Celsius is 0
0 Kelvin is Absolute Zero ( lowest temp in universe)
Kelvin scale absolute temperature
Fahrenheit is different
Intensive Property
Does NOT depend on amount (color,boiling point,freezing point, density)
Law of Conservation of Energy
Energy can not be destroyed, only changed into another
Law of definite Proportions
(1/2=50%, 1/2=50%) same proportion by mass
Substance
Matter which all samples have identical composition and proprties
Measurements in Chemistry
Length=meter (m),
mass= kilograms(Kg) , time=seconds(S) ,
Current=Ampere(A) , Temperature= kelvin(K) ,
Amount of substance=Mole(mol)
Weight
Measurement of the gravitational attraction for a body
Mass
Measurement of the quantity of matter in a body
Energy
Capacity to do work or transfer heat
Two types: potential energy and kinetic energy
1 meter
39.37 inches
Or 3.28 ft
Conversion factors of Length
1 inch = 2.54 cm
1 meter = 39.37 inches
1 meter = 3.28 ft
1 mile = 1.60 Km
Conversion factors of Volume
1gallon= 3.785 liters 1 gallon= 4 quarts 1 gallon= 2 pints 1 quart = 0.946 liters 1 pint = 0.473 liters
Conversion factors of Mass
1 pound = 453.6 g
1 Kg = 2.204 lb
1 oz= 28.34 g
Accuracy
How closely measured values agree with the correct value
Depends on operators skill and calibration of instrument
Precission
How closely individual measurements agree with each other
Depends on instrument quality and sensitivity
Precision precedes accuracy
Density
Density = mass (g)
_________
volume (ml)
D= m/ v. Or m= D x V. Or V= m/D
Significant figure rules
Leading zeroes are never significant
All non zeroes are significant
Zeroes at the end( trailing) are significant if they are preceded by a decimal point
Imbedded zeroes are significant
Fahrenheit
F= 9/5(c) + 32
Or F= (1.8 x c) +32
Specific Gravity
Same as Density, but without the symbols Ex D= 11.4 g/ ml , specific grav= 11.4 Density substitute (g/ml) \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ density of water (1.00 g/ml)