Chapter 1 Flashcards
chemistry
study of matter, properties, and changes it undergoes
macroscopic
ordinary-sized objects
submicroscopic
atoms and molecules
matter
anything w/ mass and occupies space
atoms
building blocks of matter
molecules
2+ atoms joined
gas
no fixed volume/shape, uniformly fills space, can be compressed/expanded
liquid
distinct volume, assumes shape of space, not compressible
solid
definite shape and volume, not compressible
substance (pure)
distinct properties and same composition (doesn’t vary)
elements
cannot be decomposed into simpler substance; 1 atom type w/ 1 molecule type
diatomic elements
“have no fear of ice cold beer” Hydrogen, Nitrogen, Fluorine, Oxygen, Iodine, Chlorine, Promine
compounds
can be decomposed into simpler substances; have definite composition
law of constant composition
elemental composition of compound = always the same
mixtures
2+ substances; retain chemical identity
intensive properties
independent of the amount; inherent to substance (density, boiling point, color, temp)
extensive properties
depend on amount of sample (mass, volume, energy)
physical properties
observed w/o changing identity or composition; color, odor, density, melting point, boiling point, hardness
chemical properties
only observable when substances changes/reacts (flammability)
physical change
physical appearance changes, chemical composition doesn’t (change of state, temp, volume)
chemical reaction
substance transformed to chemically new substance; reacting substances converted to new substance
filtration
separates solids from liquids
distillation
separates liquid mixture based off boiling points
chromatography
separates liquid mixture based on chemical properties
energy
capacity to do work (no mass)
work
energy transferred when force exerted on object causes mvmnt
force
push/pull
kinetic energy
energy of motion (KE= 1/2 mass x velocity)
potential energy
position/stored energy
chemical energy
released when bonds b/w atoms formed; consumed when bonds break
celsius to fahrenheit
F = (9/5)C + 32
Fahrenheit to celsius
C = (5/9) (F-32)
Celsius to Kelvin
K = C +273.15
Kelvin to Celsius
C = K-273.15
SI units
length (m), mass (kg) , temp (K), time (sec), amount (mol), electrical current (Amp), luminous intensity (cd)
mega
10^6
kilo
10^3
deci
10^-1
centi
10^-2
milli
10^-3
micro
10^-6
nano
10^-9
pico
10^-12
density
mass/volume
precision
how close measurements are together (standard deviation)
accuracy
how close 1 measurement agrees to true value
SF: zeros b/w nonzeros
significant
SF: zeros at beginning (before decimal)
not significant
SF: zeros at end (after decimal)
significant
SF: (+/-) rule
least decimal places
SF: (x/%) rule
least SF
