Unit 1: Matter, Chemical Trends, Bonding Flashcards
atomic model
- democritus - 400 BC
atomos: smallest piece of matter, “not to be cut” - aristotle/plato
earth, water, fire, air - dalton - early 1800s
atom - thomson - 1897
atom = + charge substance & - electron scattered - rutherford - 1908
nucleus + electrons orbit around - bohr - 1913
electron levels - quantum model
electrons behave like waves, do not orbit around definite path, electon clouds
atom
smallest particle of an element which retains its identities and properties
isotope
same element w/ different # of neutrons
radioactivity
spontaneous emission of radiation from nucleus of an atom
column
group/family
row
period
properties of metals
- reaction with water: form bases
- malleability: malleable/ductile
- conductivity: good
- density: high
- boiling point = high
- lustser = lustrous
properties of nonmetals
- reaction with water: form bases
- malleability: brittle
- conductive: poor
- density: low
- boiling point: low
- lustre: dull
alkali metal
group 1
very reactive, especially with water
alkaline earth metal
group 2
reactive but less than alkali metals
halogens
group 17
very reactive
halogen + water = acid
halogen + metal = salt
noble gases
gases at STP
not reactive
liquid elements
Hg, Br
gases
noble gases, O, H, N, F, Cl
ion
atom gain/lost electrons
anion
atom gain electron + negative charge
cation
atom lose electron + positive charge
isoelectronic
having same number of electrons as nearest noble gas
largest atomic radius
fr
atomis radius
left -> right = decreases
affected by:
# of protons
down: increases
affected by: # electron shells
smallest atomic radius
he
ionization energy
energy required to remove e- from valence energy level and form a cation
ie trend
left –> right: increases
bc of # of protons/size
down: decreases
bc of energy levels/size
highest IE
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