HOMO of CO
Inorganic Synthesis
3 weeks
2 syntheses
1 magnetic susceptibility analysis
Which are like yours & how do they differ?
Cobalt Syntheses
Copper Syntheses
Nickel Syntheses
Iron Syntheses
44
sodium tricarbonatocobaltate(III) 3-hydrate
46
bis-tetraethylammonium tetrachlorocobaltate(II)
8
bisethylenediaminecopper(II) nitrate
10
tetraamminecopper (II) sulfate monohydrate
11
bisethylenediaminecopper(II) diiodocuprate(I)
12
bisacetylacetonatocopper(II)
41
cis-bis glycinato copper (II) monohydrate
23
hexaamminenickel(II) fluoroborate
24
dinitrotetramminenickel(II)
42
hexamminenickel (II) chloride
43
bis(dimethylglyoximato)nickel(II)
47
tris(acetylacetonate)iron(III)
Variations in:
a) transition metals - different # of d-electrons
b) ligands
- number/geometry/strength(splitting/color)
Procedures vary, but for all the
following applies…
• DO NOT USE BUNSEN BURNERS!!!!!
• Most solvents (acids, bases, organics) are on trays
• Cart by the side bench
–
–
–
–
ethylene diamine
30% hydrogen peroxide
parafilm
product vials
– acac (2,4-pentadione, acetyl acetone)
– pH paper
– P2O5 dessicators
The balances must never be
moved and must be kept clean!!!
Make sure the bubble is centered
in the circle!
Use the analytical balance to
weigh the starting material
containing the compound with
the metal (the limiting reactant).
Other materials can be weighed
on the top-loading balances.
Notes on % Yield
You will be graded on your % yield, so work precisely.
% yield is based on the mass of starting material containing
the metal.
Ligands are added in excess.
If you have slightly less/more, it is ok.
M + XL  MLX
Carefully follow instructions for filtering and recrystallization
given in your manual to avoid excess loss of material.
Check out items from the stockroom
Request equipment by synthesis number.
Return everything clean at end of day for the next day’s
section.
Check out tubes for paramagnetic synthesis required for
week 2 or week 3 when you are ready to prep your sample.
Funnels, funnels, everywhere funnels!
Which one do you use and why?
Recrystallization
Used to purify product
Dissolve product in minimum amount of hot solvent and then cool slowly.
- too much solvent results in loss of product
Product should crystallize out because solubility lower at lower temperatures.
Products usually collected by vacuum filtration w/ Buchner funnel (& filter paper)
- choose appropriate size filter paper
- wet filter paper first with solvent
Recrystallized products usually washed with small amount of cold solvent
to remove layer of impurities adhering to crystals.
- stop suction and add cold solvent
- stir gently and then reapply suction
Drying of crystals done either in air, oven, or dessicator as described in procedure.
How do you know it is dry?
PLEASE READ LABELS
• 100% ethanol is not 95% ethanol.
• Ammonia (NH3) bottles are labeled as
ammonium hydroxide, NH4OH. Why?
• Dilute ammonia is 6M and concentrated is 15M.
• Concentrated acetic acid is the same as glacial
acetic acid.
Lastly…
• Remember to record observations (after each step
where you observe a change) in your notebook to help
determine reactions.
• Return WASHED vials for starting materials after
thoroughly cleaning them (toss the baggies).
• Week 2 - reconvene in class first to discuss
paramagnetic susceptibility.
• Week 3 - attendance is required, finish experiment,
begin report.
Have fun!
DO NOT USE BUNSEN BURNERS!!!!!
10
Week 2 & 3
• Remember reports are due 2 days after
the third week of the experiment – start
working on it this week!
• Attendance is required during week 3
• Today start the second synthesis
• Finish the first synthesis
• Paramagnetic susceptibility measurement
• Please work on the wet bench, next to the
sink, not near the balances.
Week 2- Paramagnetic Susceptibility
Two MSB-1 balances are located in the instrument
room.
Empty tubes from the stockroom to fill with your sample
Instrument room has standard sample to use for
determining constant. Record the info that is provided
and taped onto the counter.
When you are done, clean mortars & pestles and your borrowed tube
before returning to the stockroom. The vacuum line has a special tubing
to dry your glass tube.
The equations, background information, description of how the balance
works are in your manual, as you know since you’ve read it already.
The instructor or lab assistant will help the first students, then each
student must help another, etc….
12
Your products
• Turn in products to your day’s basket
• Label vials with
– Name
– Date
– Compound name/formula
– Mass
– Section
Cleaning Up
• Unplug all hotplates
• Wash starting materials vials
• Brush out spills inside the balance
• Clean up counter, especially around the
balances