3.1 electron theory Flashcards
(18 cards)
what is an atom made up of
proton
neutron
electron
what makes up the mass of an atom
proton
neutron
what happens when an atom has the same amount of protons as electrons
the atom has no electrical charge
what happens if an atom has more electrons than protons
it becomes negatively charged
what is a molecule
an electrically neutral group of two or more atoms held together by a chemical bond
what is a charged molecule called
an ion
what is a positive ion
The atom which has lost the electron has now gained an overall positive charge
what is a negative ion
When an atom gains an electron in its outer orbit it becomes overall negatively charged
how are compounds made up
when two or more elements are combined chemically
what does a good conductor contain
atoms that have less than four electrons in the outer shell
what is the pattern found in conductors called
crystal lattice
what is an example of a conductor
copper, aluminum, and silver
what is a semi-conductor defined as
a material whose conductivity is somewhere between that of a good conductor and a good insulator
what can the effectivity of a semi-conductor be affected by
temperature, doping (adding foreign atoms), or by light
when are semi-conductors better
at higher temperature
how many electrons does a semi-conductor contain
4 on their outer shell
what is an example of a semi-conductor
silicon and germanium
what is an example of an insulator
mica and porcelain
