accuracy
how close of a measurement we are to a correct value or target
precision
closeness of two and measurements to each other
quantitative
discrete, or counting, or continous or measurement. numerical .Quantitative refers to data that can be expressed as a number, allowing for statistical analysis and comparison.
qualitative
descriptive data involving sentences, based on observations. Qualitative refers to data that describes characteristics or qualities, often expressed in words rather than numbers, allowing for analysis based on subjective interpretation.
subatomic particles
smaller than an atom
proton
1.00728 = 1amo nucleus positively charged subatomic particle
electron
0.000549=0 amu orbital negatively charged subatomic particle
nuetron
1.00867=1 amu, nucleus neutral subatomic particle in the nucleus
amu
atomic mass unit
isotope
same element that have a diff. mass due to varying numbers of neutrons.
periodic law
elements, when listed by their atomic number, their chemical and physical properties repeat periodicaly
valence electrons
Electrons in the outermost shell of an atom that determine its chemical properties and bonding behavior.
aufbau principal
electrons will fill the lowest energy level first, then move to the higher ones
trends
predictable pattern or change in a particular direction
reactivity
how easily an element will combine or interact with other elements to form compounds or molecules
atomic radius
size of atom, #of energy levels, amount of proton. determines size
electronegativity
the ability of an atom to attract an electron in the outermost energy level. a change in energy levels
compound
a substance in which 2 or more different elements are bound together
molecues
diatomics/two of the same element sharing an electron
polyatomics
group of atoms bonded that act as a single atom
ends in ite/ate
written as:
sodium carbonate: Na(2)Co(2)
more than one PAI needed:
Magnesium Nitrate
Mg(NO>3)>2
ionic compounds
metals and nonmetals
electrons are transferred
compound is neutral
covalent bonds
nonmetal and nonmetal
electrons shared
compound is neutral
diatomic elements
two-atom elements
Br,I,N,Cl,H,O,F only
always X>2, as not enough electrons on own
chemical reation
change that is chemical occurs when atoms rearrange and form new substances
reactants
original substance in a chemical reation
products
the new substance made by a chemical reaction