Chemical Forums
Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: wiwa89 on January 18, 2012, 07:42:04 PM
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Hi all,
I want to ask if is possible to bring CaO ( or BaO or SrO) in some organic solution. I know that with water became CaOH but in pure organic solvent?
I have to do an esperiment..Are elements of 2 group..and the oxides (of Ca,Ba and Sr) are strong bases..
an I ask you why not? I mean what happen if I put CaO in benzene or in DMF?
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No. Can you tell why? Hint: Look at the periodic table, what sort of compounds are these?
[EDIT]
an I ask you why not? I mean what happen if I put CaO in benzene or in DMF?
You can always try it and see what happens.
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the problem is that I can't try because is for school and I don't have my own lab..the thing is that my professor asked me to find if CaO is soluble in organic solvent..
the problem is that I can't try because is for school and I don't have my own lab..the thing is that my professor asked me to find information about that (if CaO is soluble in organic solvent) and in internet or books I didn't find nothing
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I was kidding. It was a little unfair of you to edit you post after I'd already answered, so I edited mine afterward, and told you to try it. Now, what can you tell me about the general type of compounds you're trying to dissolve?
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CaO will not dissolve in any organic solvent that does not react with it. Calcium oxide, does, however, dissolve in pure ethanol (or methanol) to form calcium ethoxide, Ca(OC2H5)2 in solution. Acetone also reacts with CaO, undergoing an aldol condensation to form
CH3-CO-CH2-C(CH3)2(OH).
These types of solutions are extremely corrosive and hazardous. Be sure to wear splash proof goggles, long rubber gloves, a rubber apron, and have some vinegar ready in the event of an accident.
There are not any convenient solvents that can be used to dissolve CaO.
The short answer is that neither benzene, toluene, or any other plain hydrocarbon will dissolve CaO.
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CaO will not dissolve in any organic solvent that does not react with it. Calcium oxide, does, however, dissolve in pure ethanol (or methanol) to form calcium ethoxide, Ca(OC2H5)2 in solution. Acetone also reacts with CaO, undergoing an aldol condensation to form
CH3-CO-CH2-C(CH3)2(OH).
Is that actually true? This was a beginner's chemistry question, and I'd hoped to teach a new student something about elementary chemistry. I know that CaO doesn't dissolve appreciably in water. The electronegativities are too great for water to break the ionic bond, which I'd hoped the beginner would be able to read up on in their textbook. How is ethanol, a less polar solvent, able to break an ionic bond? Is this actually a practical war to make the pretty hazardous reagent -- calcium ethoxide? Most of the prep that I'd heard of for alky ethoxides start with the metal.
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Is that actually true?
Entirely plausible. CaO reacts with water to for calcium hydroxide, I have no reason doubt that CaO wil react with eathanol or methanol in a similar way to for the corresponding calcium alkoxide . CaO can definitely be used as a base to catalyse aldol reactions (I have second hand experience).
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Yikes, that seems like an awfully easy way to make an alkoxide. Some might even do it accidentally, using CaO as a cheap drying agent when nothing else was available.