Ch 7 & 8 Flashcards
What do valence electrons do
Form chemical bonds between 2 atoms
What is a chemical bond
A force that holds two atoms together
How do chemical bonds form
Attraction between a positive nucleus of an atom and the negative electrons of another
What is an ion
An atom or molecule with an electric charge due to the loss or gain of one or more electrons
Every atom has how many valence electrons
8
What is a cation
A positive ion that dims when an atom loses one or more valence electrons- positive because it needs to gain more electrons
Metals relationship with valence electrons?
They lose easily
What is nonmetals relationship to electrons
They gain easily
What is an anion
A negatively charged electron
What is an ionic bond
The electrostatic force that joins oppositely charged particles together in an ionic compound
What do ionic compounds hold
Metals and nonmetals
What do subscripts represent
The number of atoms in a compound
What are poly atomic ions
Ions made up of more than one atom
What is an oxyanion
A poly atomic atom is a nonmetal bonded to an oxygen atom
Ions with the greatest number of oxygen atoms end in
Ate
Ions with the fewest number of atoms end in
Ite
What is an ionic crystal
The repeated pattern of the particle packing in an ionic compound
What does strength of attraction determine
Melting and boiling point, hardness
Reactions that absorb energy
Endothermic
Reactions that release energy
Exothermic
When do chemical reactions occur
When atoms gain lose or share electrons
What creates a molecule
When nonmetals share electrons to form a covalent bond
What do covalent compounds contain
Only nonmetals
What ionic compounds contain
Both metals and nonmetals
What arranges electrons in molecules
The Lewis dot structure
What are sigma bonds
Single covalent bonds
Hydrogen can act as a metal and nonmetal why
Because it has one proton and one electron
How do single bonds form
The sharing of electrons between 2 nonmetals
Sigma bond facts:
It’s symbol is O
It is the strongest type of covalent bond
What are the diatomic molecules
H,N,O,F,Cl,Br,I all with a subscript of 2
When two pairs of electrons are shared between 2 atoms
Double bond
When 3 pairs of electrons are shared between 2 atoms
Triple bond
