chapter 8 Flashcards
nucleus of atom contains:
protons and neutrons
nucleons account for
mass
location, mass, charge of proton
- nucleus
- 1
- +1
location, mass, charge of nuetron
- nucleus, 1, neutral (0)
location, mass, charge of electron
- around the nucleus
- 1/1840 (negligible)
- negative (-1)
proton/atomic number
- number of protons in an atoms (+1)
- equal to the number of electrons (-1)
charge of an ATOM is:
neutral
atomic mass/ nucleon number
- number of protons and neutrons in the atom
configuration of soidum
- atomic number: 11
- relative atomic mass: 22.99
- 11 protons
- 11 electrons
- 12 neutrons
why arent electron’s mass not added to the mass number
- the mass of electrons are very small/negligable
isotopes definition
- atoms of the same element with the same number of protons but different number of neutrons
- affects the mass number
properties of isotopes (chemical, physical)
- same chemical properties
- different physical properties
how are electrons arranged
- around the nucleus in shells
shell maximum
- shell 1: 2
- shell 2: 8
- shell 3: 8
the outermost shell is known as the
- valence shell
electrons in the outermost shell are known as
- valence electrons
elements with the same number of valence electrons have:
similar chemical properties
electrons of the same group have:
the same number of valence electrons
electrons of the same period have:
the same number of electron shells
ions definition:
charged particles (positively/negatively)
atoms become ions through:
- gaining/losing electrons to obtain electronic structure of a noble gas
cation is
- a positive ion
- formed when an atom loses electrons
examples of cations:
- metals with 1, 2, 3 valence elcetrons
- charges: 1+, 2+, 3+
anion
- negative ion
- formed when an atom gains electrons
examples of anions:
- non-metals with 5, 6 ,7 valence electrons
- charges: 3-, 2-, 1-
why don’t group 18 form ions?
- they have completely filled valence shells
ions in the same group have:
- the same charge
