Chemistry - unit 4: Period Table

Dmitri Mendeleev

organized elements based on increasing atomic mass, errors with table, predicted properties of undiscovered elements

Mosley

organized elements based on atomic #, resolved errors in Mendeleev’s table, modern table

Groups/Families

vertical columns, 1-18

Periods

rows, top to bottom=

Elements with similar properties share the same _____

group

Elements with similarities in energy levels share the same ____

period

s-p sublevels

main, valence electrons, columns 1-2, 13-18

d sublevel

transition metals

f sublevel

inner transition metals (bottom)

Which sublevels include valence electrons?

s and p

metals

left-middle, malleable, good conductors, luster, ductile

alkali metals

group 1, 1 VE, very reactive, +1 cation, s block

alkaline earth metals

2 VE, group 2, s block, reactive, +2 cations

transition metals

middle to staircase, reactive/free elements (stand alone), d sublevel, variable ions

nonmetals

poor conductors, anions, brittle solids/gases, right side + hydrogen

halogens

group 17, very reactive, -1 anions, ns²np⁵

noble gases

group 18, unreactive, inert, stable, no ions, full shell, ns² np⁶

Mettaloids

semiconductors, staircase, properties of metals + nonmetals

valence electrons

outermost shell

stabel ocet

8 electrons in outer sehll

ions

gain/lose electrons to achieve stabel ocet

isoleectronic

element w/ charge has same electron configuration as other element

pseudoisolectronic

isoelectronic for d sublevel

Which electrons influence an element’s properties?

outermost electrons

What happens when you add electrons to core orbitals?

it results in less changes than if electrons were added to valence electrons

shielding effect

electrons in lower energy levels shield electrons in outer level from full affect of nuclear charge

atomic radius

distance from center of nucleus to outermost electrons

bond radius

2 identical elements bonded together

In which direction to atoms get larger?

down periodic table

In which direction to atoms get smaller

going across periodic table

When do ions become smaller?

when losing electrons

When do ions become positive?

when losing electrons

When do ions become bigger?

when gaining electrons

When do ions become negative?

when gaining electrons