module 2.2 up to 2.2.8 Flashcards
Does energy of shells increase or decrease as you move away from the nucleus?
increase
what is the principal quantum number?
n
what is the formula for the maximum number of electrons a shell can hold?
2n^2
where are electrons found?
in atomic orbitals
what is an atomic orbital?
a region around the nucleus which can hold up to 2 electrons with opposite spins (upspin & downspin)
what are the 4 orbitals?
s p d f
how many s orbitals are there per shell?
1
how many p orbitals are there per shell?
3, found in 2 and above
how many d orbitals are there per shell?
5, found in 3 and above
how many f orbitals are there per shell?
7, found in 4 and above
what are the max number of electrons per shell?
2,8,18,32…
what is the shape of an s orbital?
spherical
what is the shape of an p orbital?
dumb-bell
what is a subshell?
all of the orbitals of the same type in the same shell
what fills before 3d (electron configuration)
4s
why don’t orbitals pair when going into boxes immediately?
they only pair when they have to
what is the electron configuration for cobalt (27)?
1s2 2s2 2p6 3s2 3p6 4s2 3d7
~why are orbitals not filled in numerical order?
because the principal energy levels get closer together as you go further from the nucleus
what does an ion have the same of but a different amount of
ion-same amount of protons, different amount of electrons
what type of ion does oxygen form?
oxide ion
what type of ions do metals form?
positive ions (cations)
what type of ions do non-metals form?
negative ions (anions)
what is the electron configuration of sodium(11) and the sodium ion?
sodium: 1s2 2s2 2p6 3s1
na+:1s2 2s2 2p6
what do you notice about the electron configuration of ions?
all ions have the same electron configuration as noble gasses.
write the shorthand configuration of Na
[Ne]3s1
as the 4s shell fills first…
it is always first to empty ( eg for ions)
what is an ion
an atom that has gained or lost electrons- it possess a positive or negative charge
what group changes their name when becoming ions
halogens
what is the name of fluorine when it becomes an ion
fluoride
what is the name of nitrogen when it becomes an ion
nitride
what is the name of chlorine when it becomes an ion
chloride
what is the formula of the complex ion: nitrate
NO3-
what is the formula of the complex ion: sulfate
SO4^2-
what is the formula of the complex ion: hydroxide
OH-
what is the formula of the complex ion: carbonate
CO3^2-
what is the formula of the complex ion: Ammonium
NH4+
what is the formula of ammonia
NH3
what is the formula of the sulfide ion
S^2-
how many ions can transition metals form?
more than 1
how are ionic compounds formed?
when ions of opposite charge come together to form ionic compounds.
what are spectator ions?
ions that are present during a reaction but remain unchanged (present on both sides of the reaction).
Describe the structure of ionic compounds and how it occurs…
- oppositely charged ions attract each other (from all directions).
- each of these ions in turn attract more ions to form a giant lattice structure (lattice=repeating)
- billions of ions latticed together.
talk about the melting/ boiling points of ionic substances and why this is.
high melting/boiling points as it requires a large amount of ENERGY to break the many STRONG ELECTROSTATIC BONDS between IONS in the GIANT LATTICE STRUCTURE.
do ionic compounds conduct electricity when melted?why?
yes, high temp= enough energy to overcome the many strong forces of attraction between ions. Ions are free to move around within the molten compound so conducts electricity.
do ionic compounds conduct electricity when solid?why?
no, ions are fixed in position in giant lattice, can vibrate but not move so cant conduct
do ionic compounds conduct electricity in solution?why?
yes, water molecules separate ions from the lattice. Ions are free to move around in the solution, it does conduct electricity.
what do many ionic compounds dissolve in?
polar solvents eg water
why do ionic compounds dissolve in polar water molecules.
polar water molecules break down the lattice and surround each ion in solution
why might water not be able to break up a compound of ions with large charges?
the ionic attraction may be too strong so lattice structure not broken down- compound=not very soluble
when do ionic compounds have a lower solubility?
when ions hold onto each other more firmly( stronger attraction because larger charge)
what are isotopes
atoms of the same atomic number (protons) but a different mass number (neutrons)
~what is Ar/Mr
relative atomic mass/ relative molecular mass
how do u calculate Ar (isotopes)
Ar= (isotope mass x percentage)+(isotope mass x percentage)/100
are covalent bonds strong?
yes
why are covalent bonds strong?
because of the ELECTROSTATIC forces between the shared negatively charged electrons and the positively charged protons in the nucleus of each atom
state how covalent bonds are formed…
covalent bonds are formed when orbitals, each containing one electron overlap. this forms a region in space where an electron pair can be found
the greater the overlap of oribitals, the stronger the…
… bond
talk about the covalent attraction of H2
in H2, the attraction is soley between the shared pair of electrons in the covalent bond and the nuclei of the atoms~
how many covalent bonds does nitrogen form?
3
whats it called when nitrogen contributes both electrons in the double bond?
coordinate bond/ dative covalent bonds
whats a dative covalent bond?
a shared pair of electrons where BOTH electrons have been donated by one atom
what does average bond enthalpy serve as
a measurement of covalent bond strength.
describe the melting/boiling points of simple covalent structures
- have weak intermolecular forces so not a lot of energy to break
- covalent bonds within the molecules are strong and cant be broken easily.
are simple covalent structures good at conducting electricity? why?
NO because there are no mobile charge carriers, ions or electrons to carry electric charge
what are simple covalent structures soluble in?
non-polar substances such as hexane
name 4 giant covalent structures…
diamond, silicon dioxide, graphite, graphene
diamond: talk about its melting point
high due to network of very strong carbon-carbon covalent bonds which has to be broken before melting occurs
diamond: talk about its density
v dense due to carbon atoms packed close together
diamond: talk about its solubility
insoluble in water and organic solvents- no possible attractions
why are diamonds rare
major heat and pressure needed
talk about the formation of graphite
each carbon atom forms covalent bonds to 3 other carbon atoms, forming a layer structure
graphite: talk about melting point
high( lots of energy to break strong covalent bonds)
graphite: talk about how it feels
soft and slippery as layers of covalently bonded carbon atoms can slide over each other
graphite: talk about its solubility
insoluble
graphite: talk about its conduction of electricity
delocalised electrons free to move throughout the sheets carrying charge
describe graphene
single layer of graphite, strong covalent bonds, excellent electrical conductivity.
talk about the solubility of nitrates
nitrates are always soluble
talk about the solubility of halides
halides are soluble with everything except lead, silver and mercury
electron config of cr atom
1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^5
electron config of cr3+ atom
1s^2 2s^2 2p^6 3s^2 3p^6 3d^3
electron config of copper atom
1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^10
electron config of cu+
1s^2 2s^2 2p^6 3s^2 3p^63d^10
electron config of cu2+
1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^9
