Studied by 2 peoplenucleon number
What is another name for the mass number?
proton number
What is another name for the atomic number?
atom of the same element with the same atomic number
and a different number of neutrons
relative to the mass of 1/12 of a carbon-12 atom
How is relative atomic mass measured?
+1
What charge are ions in a mass spectrometer?
m/z (mass / charge)
What unit is given by a mass spectrometer?
organic compound
What type of compound produces an M+1 peak?
carbon-13 is present in small amounts
Why are M+1 peaks seen in mass spectrometry?
s
p
spherical
What shape are s-orbitals?
elongated dumbbells
What shape are p-orbitals?
chromium and copper
Which elements have unusual electronic configurations including 4s1 where 4s2 may be expected?
4s
Which shell fills up first? [3d/4s]
2p
Which shell fills up first? [2p/3s]
orbitals in a subshell receive one electron
then two before moving onto the next subshell
A(g) -> A+(g) + e-
What is the equation for first ionisation energy (IE1)?
A+(g) -> A2+(g) + e-
What is the equation for second ionisation energy (IE2)?
energy needed to remove one mole of the outermost electrons from one mole of gaseous atoms to produce one mole of gaseous ions with a charge of +1
What is the definition of first ionisation energy (IE1)?
group 1
An element has a large jump between IE1 and IE2. What group is the element?
group 3
An element has a large jump between IE3 and IE4. What group is the element in?
orbital
nuclear charge
outermost electron is in an s-orbital
What is an s-block element?
outermost electron is in a p-orbital
What is a p-block element?
outermost electron is in a d-orbital
What is a d-block element?
covalent radius
What is the distance between two covalently bonded nuclei?
van der Waals radius
What is the distance between two non-bonded nuclei?
high melting temperature
good conductivity
there are many forces of attraction
Why do metals have high melting temperatures?
delocalised electrons can carry a charge
Why do metals have good electrical conductivity?
delocalised electrons and cations can pass kinetic energy along the metal
Why do metals have good thermal conductivity?
layers of cations can slide past one another
Why are metals malleable and ductile?
attraction between oppositely charged ions > repulsion between like charged ions
How are ions arranged in an ionic solid?
small
Which ions make stronger ionic bonds? [Large/Small]
negative
What sign is the charge on an anion?
positive
What sign is the charge on a cation?
combined electrostatic forces of attraction among all ions is large
Why do ionic compounds have high melting temperatures?
ions repel when layers slide
Why are ionic compounds brittle?
no delocalised electrons
ions cannot move
ions are mobile and will move to opposite electrodes
Why are ionic liquids good electrical conductors?
lithium nitride (Li3N)
batteries
electrolysis
What is used as evidence for the existence of ions?
end-on
What type of overlap causes sigma bonding?
s-orbitals
p-orbitals
sideways
What type of overlap causes pi bonding?
p-orbitals
Which orbitals can undergo pi bonding?
double or triple
What type of covalent bonds are pi bonds?
ability of an atom to attract a bonding pair of electrons
What is electronegativity?
up a group
across a period
different electronegativities
What causes covalent bonds to be polar?
electrically neutral group of two or more atoms held together by chemical bonds
What is a discrete (simple) molecule?
empty orbital of one atom overlaps with an orbital containing a lone pair
How is a dative covalent bond formed?
false
lone pair-lone pair repulsion < lone pair-bond pair repulsion [True/False]
true
lone pair-bond pair repulsion > bond pair-bond pair repulsion [True/False]
true
bond pair-bond pair repulsion > lone pair-lone pair repulsion [True/False]
180
What is the bond angle for linear molecules?
120
What is the bond angle for trigonal planar molecules?
109.5
What is the bond angle for tetrahedral molecules?
107
What is the bond angle for triagonal pyramidal molecules?
104.5
What is the bond angle for V-shaped molecules?
90
120
90
What is the bond angle for hexagonal molecules?
dipoles cancel
Why is carbon dioxide not a polar molecule?
dipoles reinforce
What makes a molecule polar?
London forces
What name is given to instantaneous dipole-induced dipole interactions?
van der Waals forces
What is another name for London forces?
shifting electron density
What causes an instantaneous dipole?
atomic number / number of electrons
Strength of London forces increases as ... increases
sometimes attract
sometimes repel
more electronegative than hydrogen
The atom bonded to hydrogen has to be ... to undergo hydrogen bonding
alcohol (OH)
All compounds containing which group can undergo hydrogen bonding?
between a hydrogen and the lone pair of electrons on oxygen
Where is the hydrogen bond in water?
between a hydrogen and the lone pair of electrons on nitrogen
Where is the hydrogen bond in ammonia?
CnH2n+2
What is the general formula of alkanes?
increased significance of London forces
more point of contact
CnH2n+1OH
What is the general formula for alcohols?
alcohols
hydrogen bonding
HF
Which hydrogen halide has the highest boiling temperature?
increases
From HCl -> HBr -> HI boiling temperature... [Increases/decreases]
hydrogen bonding
Why does water have a high boiling temperature?
fewer hydrogen bonds per molecule
Why does HF have a lower boiling temperature than water?
gaps between molecules
Why is ice less dense than water?
particles separated & surrounded by solvent particles
strong force of attraction between solute & solvent
non-polar
what types of molecules are insoluble in water?
like dissolves like
What is the rule of thumb for solvents?
giant metallic lattice
"High melting temperature
giant ionic lattice
"High melting temperatures
giant covalent lattices
What are diamond
sigma bonds
What bonds are present in diamond?
109.5
What is the bond angle in diamond?
high melting temperature
hard
graphite
Which giant covalent lattice is a good solid lubricant?
can only conduct parallel to layers
What is unique about graphite's ability to conduct electricity?
single layer of graphite
What is graphene?
molecules arranged in a regular pattern
Why is solid iodine crystalline?
molecular lattices
What are ice and solid iodine examples of?
only London forces need to be overcome
Why do molecular solids have low melting temperatures?
covalent bonding
Which type of bonding can result in either a giant lattice or a discrete molecule?
oxidation
What is the loss of electrons called?
reduction
What is the gain of electrons called?
it is reduced
What happens to an oxidising agent in a reaction?
Note
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