Vocab
when two or more atoms share an electron is called
what is a covalent bond
a group of two or more atoms bonded together that acts as a single unit with an overall positive or negative charge
what is an ionic bond
Explain why neon is monatomic but chlorine is diatomic
because it is a noble gas with a full outer electron shell, making it stable and unreactive as a single atom
Why are metals good conductors of electricity
their electrons are not tightly bound to any single atom, but instead form a "sea" of delocalized electrons that can move freely through the metal's structure
a neutral chemical compound formed from oppositely charged ions, which are held together by a strong electrostatic attraction known as an ionic bond
what is a ionic compound
Explain why ionic compounds are electrically neutral
the total positive charge from their cations is exactly balanced by the total negative charge from their anions
water has this many covalent bonds in one molecule of H2O
what is 2
why the properties of all steels are not identical
because steel is an alloy of iron and carbon, and its specific properties are determined by the varying amounts of carbon and other alloying elements, as well as the steel's heat treatment and processing
the eight electrons in an atom's outermost shell
what is an octet
Most ionic substances are brittle why?
their strong electrostatic attraction creates a crystal lattice structure that is rigid
characterize a coordinate covalent bond
a type of chemical bond where both shared electrons originate from a single atom
This metal is a common example used to illustrate metallic bonding
what is copper
a model describing metallic bonding, where the outer electrons of metal atoms are delocalized and move freely in a "sea" around a lattice of positive metal ions
what is a sea of electrons
Identify the kind of ion that form lithium oxide, Li2O
lithium cations and oxide anions
how many electrons do two atoms in a double covalent bond share? how many in a triple covalent bond
in double covalent bonds 4 and in triple covalent bonds 6
Name some alloys
steel and cast iron
a group of two or more atoms covalently bonded together that acts as a single unit with an overall positive or negative charge
what is a polyatomic ion
Explain why molten MgCl2 does conduct an electric current although crystalline MgCl2 does not
Ions are free to move in Molton MgCl2
what is bond dissociation energy
he energy required to break a chemical bond in a molecule
name the three crystal arrangements of closely metal atoms
bcc,fcc,hcp