atomic structure and periodic table

everything from atomic structure and the periodic table

overview:

• an atom has three smaller particles called sub atomic particle

• the central nucleus contains protons and neutrons

• the shells have electrons

• they have no electric change because they contain the same number of protons and electrons

• always has the same number of protons

atom

the smallest particles of an element

molecules

are atoms that form strong bonds with each other

proton

• in the nucleus

• charge +1

• relative mass 1

• the same number with electron

neutron

• in the nucleus

• charge 0

• relative mass 1

electron

• in the shells

• charge -1

• relative mass is roughly 0

• you can find the electronic configuration

atomic

• the atom its identity

• the number of protons

mass number

• be the bigger number

• number of protons + number of neutrons

• normally the weighted average mass

elements

have one type of atom

isotopes

atoms of the same elements with a different number of neutrons

weighted average mass

an element compared to carbon 12 which has a mass of exactly of 12

relative atomic mass

(mass number of isotope) x (percentage abundance of isotope)/ 100

groups

• columns in the Periodic Table

• the elements in the same group have the same number of electrons in the outer shell

• have similar chemical reactions because they have the same number of electrons in their outer shell

periods

• horizontal in the Periodic Table

• the elements in the same periods have the same number of shells

group 0

• the elements were to have another shell there will be zero elements in the next shell

• they do not easily react as they have no tendency to gain, lose or shave electrons in the outer shell

chemical reactions

atoms often gain or lose electrons to complete their outer shells

metals

• good conductors of heat

• form basic oxides- reacts with acids to form salts

• on the left side of the stairs on the Periodic Table

• 1,2,3 electrons in their outer shells

nonmetals

• arent good conductors of heat (except graphite and silicon)

• form acidic oxides- reacts bases/ alkalis to form salt

• on the right side of the stairs on the Periodic Table

• 4,5,6 or 7 electrons in their outer shells