ion Flashcards
What is the difference between an atom and an ion?
An atom has the same amount of protons and electrons. However if the atoms outer-shell is incomplete, the atom will take electrons from another substance or lose electrons to fill its outer-shell, unbalancing the number of protons and neutrons, causing the atom to become and ion.
how does a negative ion form
A negative ion forms when an atom takes electrons to fill it’s outer shell, meaning there are more electrons than protons and therefor creating a negative charge
How does a positive ion form?
A positive ion forms when an gets rid of its valence electrons to create a new outer shell (or valence shell), meaning there are more protons than electrons and therefor creating a positively charged ion
lost an electron
positive charged cation
more protons than electrons
positive
gained electron
negatively charged anion
less protons than electrons
negative
what are the ionic charges
group 1: +1
group 2: +2
group 13: +3
group 4: does not participate in ionic bonding, only covalent
group 15: -3
group 16: -2
group 17: -1
what is so special about noble gases
they are stable, and therefore have no atomic charge
how are compounds formed
compounds are formed when different types of atoms are chemically bonded together
what are the two types of bonding
covalent and ionic compounds
what types of atoms are in covalent compounds
only non-metals
what types of atoms form ionic compounds
metal + non metal (cation and anion)
bonding that occurs in covalent compounds
covalent bonding - electrons shared to form bonds
what is an example of covalent bonding
water, ammonia, carbon dioxide
how to determine whether a compound is ionic or covalent
if the substance contains only non-metals it is covalent. If the substance contains metal/s and non-metal/s it is ionic
bonding that occurs in ionic compounds
ionic bonding - electrons are exchanged to form ions which they then attract
example of ionic compounds
table salt = sodium chloride NaCl
rust = iron oxide Fe2O3
how to name ionic compounds
Metal (positive cation) is written first
Non-metal (negative anion) is written last
Anion’s name changes its ending to add -IDE
covalent compounds
Element furthest to the left of periodic table is written first
Add –IDE to last element
Look at any subscript numbers to determine which prefix/s to use
suffixes
Mono-: 1 (e.g., carbon monoxide, CO)
Di-: 2 (e.g., carbon dioxide, CO₂)
Tri-: 3 (e.g., nitrogen trioxide, N₂O₃)
Tetra-: 4 (e.g., silicon tetrachloride, SiCl₄)
Penta-: 5 (e.g., phosphorus pentachloride, PCl₅)
Hexa-: 6 (e.g., sulfur hexafluoride, SF₆)
Hepta-: 7
Octa-: 8
Nona-: 9
Deca-: 10
Note: The “mono-“ prefix is omitted for the first element if there’s only one atom (e.g., CO is carbon monoxide, not monocarbon monoxide).
naming formulae with polyatomic ions
Most polyatomic ions have a negative charge.
Ammonium is the only exception – positively charged cation
If a negative charged polyatomic ion bonds with a non-metal = covalent naming
If a positive charged polyatomic ions bonds with a non-metal = ionic naming
writing ionic compounds
the swap and drop method involves swapping the number forms the charged on the ions and dropping these numbers to give you the number of each type of ion in the compound
writing covalent compounds
Look at the worded formula and identify how many atoms of each element there are
Add pre-fixes
