Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
28 Cards in this Set
- Front
- Back
|
matter
|
anythign w. mass that takes up space
|
|
|
substance
|
smallest particle-all samples are identical
element or compound |
|
|
element
|
all atoms of one element have the same # of protons
|
|
|
compound
|
chemical combination of elements, can NOT be separated by physical means
|
|
|
mixture
|
combination of elements
CAN be separated by physical means (evaporation, magnetism etc) |
|
|
heterogeneous
homogeneous |
hetero--uneven mixture, not all samples are the same
homo-all samples are the same, evenly spread |
|
|
solid
liquid gas |
solid- little movement of atoms, definite shape and volume
liquid- movement of atoms, definite volume gas-lots of movement of atoms, indefinite shape and volume |
|
|
chemical change
physical change |
chem-changes the way atoms are bonded, creates a new subs
phys-change in the physical state (solid, liquid, gas) |
|
|
atom
|
smallest particle of an element
|
|
|
atomic mass
atomic number mass number atomic mass unit |
atomic mass--avg mass of all naturally occuring isotopes
atomic number- # of prortons, identity of atom mass #-# of protons plus # of neutrons Atomic mass unit (amu)-weight of proton/neutron--1/12 of Carbon-12 |
|
|
proton
neutron electron |
proton-wieght of 1 amu, positively charged, found in the nucleus
neutron-no charge, in the nucleus, weight of 1 amu electron-negativley charged,little weight, orbits nucleus |
|
|
isotope
|
atoms with the same atomic mass, but different mass numbers. Atoms of the same element with different numbers of neutrons
|
|
|
Fusion
Fission |
Fusion-2 nuclei combine to create one larger nucleus
Fission-One nucleus splits off into two smaller nuclei, often emits stray neutrons |
|
|
radiocactive decay
|
Hw unstable nuclei achieve stability
|
|
|
alpha
beta positron gamma |
alpha-emits alpha particle
atomic # -2 mass # -4 beta-emits beta particle atomic # +1 mass # 0 change Positron-emits positron atomic # -1 mass # 0 chage Gamma-emits energy |
|
|
half-life
|
The amount of time it takes for half a sample of a given substance to decay
|
|
|
Where is most of the mass of an atom?
|
Nucleus
|
|
|
What particles are heavy? light?
|
Protons and Neutrons are heavy
electrons are light |
|
|
Why does the nucleus stay together?
|
protons repel eachother BBUT
nuclear force (is stonger) attracts protons and neutrons to eachother |
|
|
What makes a nucleus stable?
|
small isotopes # of neutrons (N) = number of protons (Z)
large isotopes N/Z =1/1.5 |
|
|
Law of Conservation of Mass, Energy
|
Mass and energy cannot be creeated or destroyed EXCEPT in nuclear reactions, when mass and energy are interchangeable
|
|
|
(change in)e=(change in)mc2
|
c=speed of light (3*10^8 m/s)
m-mass e=energy |
|
|
Mass Defect
|
if mass goes down, energy goes up
if energy goes down, mass goes up |
|
|
Einstein
|
e=mc2
energy and mass are interchangeable time is dependent on the speed of light |
|
|
Faraday
|
electromagnetism
light=electromagnetic wave |
|
|
Lavoisier
|
law of conservation of mass
interchangeable physical states separated hydrogen and oxygen |
|
|
Meitner
|
discovered fission
atoms can be broken up |
|
|
Divisions of matter
|
Matter --> substance & muxture
Substance-->element & compound Mixture-->homogeneous & heterogeneous homogeneous mixture=solution |
