Zusammenfassung der Ressource
Atomic Structure
- The nucleus
- Protons
- Charge +1,
mass 1
- No of protons
determines what
element an atom is
- Neutrons
- Charge 0, mass 1
- Isotopes of an
element have the
SAME NO OF
PROTONS BUT
DIFFERENT NOS OF
NEUTRONS
- Have the SAME
chemical properties
as they have the
same number of
electrons
- Electrons
- Charge -1, mass v. small (1/1836 - approx. 0)
- ATOMS of an
element have equal
numbers of protons
and electrons
- Atoms can gain or lose
electrons to become
IONS
- Metal atoms lose
electrons to become
positive ions - CATIONS
- Non-metal atoms
gain electrons to
become negative ions
- ANIONS
- Orbit the nucleus in energy "levels" or "shells"
- A full outer energy shell is stable
- Noble gases have full outer
shells and are unreactive or
INERT
- Electrons fill the inner
energy levels before filling
the outer energy levels
- Maximum no of electrons in each
energy level = 2,8,8
- Row on periodic table
(period) = no of
electron shells
- Group no on periodic
table = no of electrons
IN OUTER SHELL