Chem - 7/8 (bonding) Flashcards
what s bonding
how and why atoms come together to make compounds
how many types of bonding are there
2
what are the two types of bonding
ionic and covalent
what happens to the electrons in ionic bonding
electrons are transferred
what are valence electrons
the electrons on the very outside of an atom
why do the noble gases typically not react
they have a full outer shell of valence electrons
how many valence electrons do most elements want
8
how many valence electrons does hydrogen want
2
how many valence electrons does Helium have
2
would lithium and fluorine form an ionic compound
yes
would potassium and helium form an ionic compound
no
is CO2 ionic
no
is CaS ionic
yes
what are 3 properties of ionic compounds
most are crystalline solids at room temperature
generally have high melting points
can conduct an electric current when melted or dissolved in water
why are ionic compounds typically solids at room temperature with high melting points
bc of the orderly arrangement of their ions
each ion is attracted to the ion it is next to so there is less repulsions which results in a stable structure
why are ionic solids able to conduct electricity when melted or dissolved in water
the ions are free flowing
how can you model the valence electrons of metal atoms
as a sea of electrons
what is an alloy
a mixture composed of two or more elements, at least one of which is a metal
why are alloys important
their properties are often superior those of their component elements
is the formation of an alloy a chemical or physical change
physical because its a mixture and you can separate it into its components
what information does a molecular formula provide
how many atoms of each element a substance contains
what is a molecule
a neutral group of atoms joined together by covalent bonds
what is a molecular compound
a compound that is composed of molecules
what is the difference between ionic and covalent bonds
ionic bonding involves the transfer of electrons while covalent bonding involves the sharing of electron
Does a molecular formula tell you anything about the structure of a molecule
No
Does a molecular formula tell you anything about the structure of a molecule
No
What representative units define molecular and ionic compounds
MC is molecule
IC is a formula unit
Compare and contrast melting and boiling points of molecular and ionic compounds
MC have lower melting and boiling points
Compare and contrast the states of matter of molecular and ionic compounds
Many MC are gases or liquids at room temperature, while many IC are crystalline solids
What is a single covalent bond
A bond formed when two atoms share a pair of electrons