Chapter 6 Flashcards
(32 cards)
Antoine Levoisier
listed all known elements
4 categories
John Newlands
organized the elements, increasing atomic mass
law of octaves
not accepted
Dmitri Mendeleev
atomic mass and properties correspond
predict properties and existence
left spaces where unknown elements go
Henry Moseley
periodic law
fundamental quantity
atomic number with x-rays
columns
groups
rows
periods
representative elements
1, 2, 13-18
metals
solid shiny conductive malleable ductile
nonmetals
gases
brittle
dull
poor conductors
metalloids
brittle
solid
shiny
semi conductors
corresponds with group
valence electrons
what indicates energy level
period
groups have similar
properties
4 different sub levels
s
p
d
f
no definite shape
electron cloud
size decreases going
left to right
size increases going
up to down
ions
charged particles
lose or gain electrons
larger ions
negative
Johann Dobereiner
groups of three
triads
atomic size
1/2 the distance between nuclei of two atoms of the same element when joined
shielding effect
further from the nucleus, less of a pull
electronegativity decreases
going down
electronegativity goes up
left to right
