booklet 2-bonding Flashcards
when are bonds formed
when atoms react
what are bonds
“glue” that holds atoms together
what are three things that can happen to electrons in bonding
lost gained or shared
what are the three types of bonding
ionic covalent and metalic
what sort of atoms does ionic bonding take place with
metals and non metals
what happens to electrons in ionic bonding
they are lost or gained +or-
how do metals behave im ionic bonding
they loose their outer electrons to become positive ions and have a full outer shell
what happens when an alkali metal like sodium reacts
-what charge and why
it looses its outer electron to have a +1 charge as it now has one more proton than electron
what do we call this charged atom (sodium in this case)
an ion - positive sodium ion
how do none metals behave
they gain the outer electrons off the metals to gain full outer shells and become-1 charge negatively charged ions
what happens when a halogen like chlorine reacts
group 7 element gains one outter electron
what is the charge of a chloRIDE ion
-1
what does it have the same electron configuration as
a noble gas
where do metals loose their outer electron to
non metals
why are they happy to gain the electron
to gain a full outer shell
what do they both now have
full outer shells
what ions do metals form
positive +1
what ions do non metals form
negative-1
these oppositely charged ions what
attract
by what forces do they attract
electrostatic attraction forces
what are the valencies of a metal
the same as the group number
what are the valencies in a non metal
8 minus the group number
valency is the same as what
valency is the same as the charge of an atom
ionic compounds are formed between what
metals and non metals
positive and negative ions form what
ionic bonds
what do these ionic bonds between positive and negative ions form
a giant ionic lattice
electrostatic forces of attraction are acting in what
all six directions-3dimensons
how strong are the electrostatic forces of attraction
they are strong
what does it give the compound
high melting and boiling points
ionic compounds conduct what
electricity
when do they conduct this
when molten or dissolved in water
why will they conduct this
because electrostatic forces are broken and charged ions are free to move and carry current
when will they not conduct
ionic compounds will not conduct electricity when solid as ions cannot move so cannot carry current
what sort of elements does covalent bonding take place in
non metal and non metal
what are non metals short of
non metals are short of electrons in their outer shell and they require full shells to be happy
what do they do with electrons if a metal is not present to give an electron
they share electrons in pairs with another non metal
what is made when the electrons are shared
a covalent bond is made
what is to be remembered about covalent bonds
covalent bonds are STRONG
what to ways can yu show covalent bonds
dot and cross form
stick form
what elements does metallic bonding take place in
metals and metals
what do metals conduct
heat and electricity
why do metals conduct heat and electricity
because their electrons in their outer shells are free to move and carry current
what do metals form structure wise
a giant lattice of positive ions in a sea of delocalised electrons that are negative
what do the electrons do in metallic bonding
they are free to move enabling heat and electricity to be conducted this movement also meants they attract deattract and reattract to each atom as they move about
what holds the atoms
forces of electrostatic attraction
what structure to the forces of electrostatic attraction hold the atoms in
in a regular structure
what are the forces like
very strong and hard to break
what do strong forces of electrostatic attraction result in
high melting points and hight boiling points
what does the regular structure of the metals result in
the layers of atoms can slide over eachother and metals can be bent and shaped they are malleable
what are alloys
alloys are mixtures made from two different metals
what happens when you add different size metals
different size metals distort the regular structure of pure metal and the layers cannot slide
what are alloys conpared to pure metals
alloys are harder than pure metals
what are the bonds like between solids particles
strong bonds
what do solids require a lot of to change and what to
solids require a large about of heat energy to melt from a solid to a liquid so it has a high melting point
what happens if the bonds in liquid particles are strong
they will require a large amount of heat energy to boil or evaporate the liquid to a gas
what two things does the strength of bonds depend upon
1- nature of thr particle
2-type of bonding holding together particles
ionic compounds only contain what with what
strong ionic bonds which have a high melting point
giant covalent structures contain only what and boiling point
covalent bonds with high melting point
some covalent structures also have what
weak forces of attraction between molecules
what are these forces also called
intermolecular forces or van der waals
what happens to these forces when a covalent structure melts and at what temperature
forces break and usually at a low temperature
