2.2 Flashcards
What has To exist for hydrogen bonding to happen?
1) hydrogen
2) a NOF
Oxonium ion?
H30+
What is an orbital?
A region in space where one is likely to find an electron, each orbital can hold up to 2 electrons
What are the physical bonds from weakest to strongest ?
Induced dipole dipole
Permanent dipole dipole
Hydrogen bonds
how many electrons can an f orbital show?
14
how many electrons can a d orbital show?
10
how many electrons can a p orbital show?
6
how many electrons can a s orbital show?
2
how many electrons can the 1st shell hold?
2
how many electrons can the 2nd shell hold?
8
how many electrons can the 3rd shell hold?
18
how many electrons can the fourth shell hold?
32
what is the order of energy levels, going up?
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 4d, 4f…
what does ionic bonding involve?
electrons being transferred from the metal atom to the non metal atom, allowing the elements to obtain noble gas configurations.
what does something have to have to hydrogen bonds?
hydrogen and a NOF (nitrogen oxygen fluorine)
how does hydrogen bonding work?
- h-bonds are the strongest type of IMF
- there is a large difference in electronegativity between the hydrogen and NOF, resulting in very strong dipole-dipole interactions called a hydrogen bond between molecules.
define orbital.
a region of space in which you are likely to find an electron, it can hold up to 2 electrons with opposite spin.
what is the shape of an s orbital?
spherical
what is the shape of a p orbital?
dumbell
what happens to distance between principal energy levels as you get further from the nucleus?
get closer together
what are the exceptions of the electron configuration rules?
CHROMIUM
COPPER
what is electron configuration of chromium?
1s2 2s2 2p6 3s2 3p6 4s1 3d5
what is the electron configuration of copper?
1s2 2s2 2p6 3s2 3p6 4s1 3d10
what is the rule for configurations of first row transition metals ?
when becoming ions, the electrons in the 4s orbital are removed before any electrons in the 3d orbitals.
eg: Ti+: …4s1 3d2
Ti2+: … 3d2
what are the 3 physical bonds, from weakest to strongest?
1) induced dipole dipole
2) permanent dipole dipole
3) h-bonds
what is the structure of ionic compounds?
-each ion attracts oppositely charged ions from all directions, forming a giant ionic lattice
why do ionic substances have a high melting and boiling point?
there are strong electrostatic forces between the positively and negatively charged ions. Therefore lots of heat energy is needed to overcome these forces.
are ionic substances soluble in water?
yeah
can ionic substances conduct electricity?
if they’re molten or aqueous.
are ionic substances brittle?
yes
why are ionic substances soluble in water?
water is a polar molecule. the partially negative oxygen atoms attract positive metal ions. partially positive hydrogen atoms attract negative non-metal atoms, causing it to dissolve.
why are ionic substances brittle?
if you move a layer of ions, you get ions of the same charge next to eachother. the like charges repel eachother and the crystal breaks up.
nitrate?
NO3-
sulphate?
SO4 2-
carbonate?
CO3 2-
hydroxide?
OH-
ammonia?
NH4+
silver ion?
Ag+
zinc ion?
Zn 2+
why are covalent bonds very strong?
electrostatic forces between positively charged protons in the nucleus and the negatively charged electrons in both atoms.
what is the effect of lone pairs on shape?
lone pairs cause extra repulsion, so bond angles are 2.5 degrees less as the other bonds are squeezed together.
what is the shape called when it’s based on tetrahedral but has 1 lone pair?
pyramidal
what’s the shape called when it’s based on tetrahedral but has 2 lone pairs?
angular or bent
what is the electron repulsion theory?
the shape adopted by a simple molecule or ion is that which keeps repulsive forces to a minimum.
what is the shape called when 1 atom is bonded to 3 others?
trigonal planar
what is the shape called when 1 atom is bonded to 4 others?
tetrahedral
what is the shape called when 1 atom is bonded to 6 others?
octahedral
what is the bond angle of tetrahedral?
109.5
what is the bond angle of octahedral?
90
what is the bond angle of trigonal planar?
120
why are simple covalent molecules a gas at room temperature?
they are small molecules so there are few IMFs between the molecules. little heat energyis required ti break the molecules apart. this means the substance as a low boiling point and is a gas at room temperature.
what is disproportionation?
Oxidation and reduction of the same element.
what is ionic bonding?
The electrostatic attraction between oppositely charged ions.
what is covalent bonding?
Strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms
what is metallic bonding?
The electrostatic attraction between positively charged metal ions and the sea of delocalised electrons
when explaining trends in melting/boiling points, always say…
…THEREFORE MORE/LESS ENERGY IS NEEDED TO BREAK IMFS
when explaining shapes always say…
…pairs which REPEL
READ THE FUCKIN QUESITON IN THE EXAM SKJHDASLKHDSAKFDSLAKDFSHDLFSK
yah
yeet
why are alcohols soluble in water?
they form HYDROGEN BONDS with the water
WHAT DO YOU HAVE TO REMEMBER ABOUT POLAR MOECULES
THEYRE NOT SYMMETRICALLLLL
is nitrogen diatomic?
ye
what bond is weaker sigma or pi
PI
P FOR PEAK
what bond is stronger sigma or pi
SIGMA
S FOR STRONG
Why is ice less dense than water ?
Ice has an OPEN lattice, molecules in ice held apart by h-bonds.
What kind of lattice does KBr have ?
GIANT ionic
What kind of lattice does ice have ?
Simple molecular
write an ionic equation for silver nitrate forming a precipitate with iodide.
Ag+ + I- —> AgI
what is the ion responsible for bleaching?
ClO-
what’s a disadvantage of using chlorine in water purification?
chlorine compounds are carcinogenic/toxic/poisonous
how do induced dipole dipole interactions arise?
- uneven distribution of electrons
- causes instantaneous dipole
- causes induced dipoles in neighbouring molecules.
always do the full definition of orbital
do it
WHAT DO YOU HAVE TO REMEMBER ABOUT DRAWING H BONDS
THEY COME FROM THE LONE PAIRS
when describing metallic bonding, always say…
DELOCALISED ELECTRONS
WHEN USING BRADYS TO TEST FOR A SPECIFIC CO WHAT DO U DO
IT FORMS A ORANGE PPT. PURIFY THE PRODUCT ABD COMPARE MELTING POINT OF CRYSTALS TO KNOWN VALUES.
HOW DO U DESCRIBE NON METAL MOLECULES
SIMPLE COVALENT
