Test 2: Ionic Compounds Flashcards
Compounds
two or more atoms bonded to produce a new pure substance
When a compound gains or loses electrons, it forms an
ion
Ion
an atom carrying a charge
cation
positively charge ion
anion
negatively charged ion
Which group of elements are very stable and unreactive and have full shells
Noble gases
Octet rule
noble gases have 8 valence electrons in their outer shells
usually group 4 atoms do not form __ at all.
ions
We will not predict what type of ion will be formed by a transition metal atom because
it does not follow a uniform pattern
Polyatomic ions
An ion that contains more than one covalently bonded atoms.
What are the 18 common polyatomic ions?
hydronium ammonium, acetate, cyanide, hydroxide, hypochlorite, perchlorate, nitrate, nitrite, carbonate, hydrogen carbonate, phosphate, hydrogen phosphate,
Dihydrogen phosphate, sulfate, Hydrogen sulfate, Sulfite, Oxalate
Every time we see a compound formed with a metal and a non-metal we know it is an
ionic compound
Every time an ionic compound dissolves in water the ions
separate
dissociation
an ionic compound dissolves in water
Electrolytes
Solutions with ions dissolved in them that conduct electricity
What unique property do solutions with dissolved ions have
the solutions conduct electricity
ions with multiple charges may end up attracting
multiple atoms
Whenever an ionic compound forms the overall charge must be
neutral, or zero
What questions do I ask to find the formula for an ionic compound?
What is the charge of the anion and cation?
What is the lowest possible ratio of cations:anions to make a net charge of 0?
Determining a balanced formula of an ionic compound means
Determining the type and quantity of each ion
Special care must be taken to distinguish polyatomic ions, when writing a balanced ionic compound formula. This is done by placing what around groups of atoms?
(Parenthesis)
ie. Ba3(PO4)2
we can use the charge of an ion we do know to
help us determine the charge of an ion we do not know
When looking at a compound, cations are always listed __ and metal atoms always form __
first, cations
Common properties of ionic compounds? (4)
Brittle, crystalline solid, high melting point, solutions conduct electricity
Ionic compounds are held together by electrostatic attraction rather than forming
discrete neutral molecules
The charge of polyatomic ions must be
memorized
the charge of ionic compounds WITH polyatomic ions must be
neutral
Polyatomic ion charge is determined by
the formation of bonded ions
Ionization energy and electron affinity ___ as we go across or up the periodic table
increase
Ionization energy
the energy you must put in to remove an electron and create a cation
