If you think to an anhydrous salt this is a salt which doesn't contain any water in the crystalline structure.
RaCO3 is a salt
acid anhydride
anhydride is polar acceptor
Maleic Anhydride.
An anhydride is not an acid and not a base.
Trifluoromethanesulfonic anhydride = (CF3SO2)2O
An anhydride is a compound formally derived from another by the loss of a water molecule.
It use to reduce the part of phthalic anhydride
Nitric acid does not form the anhydride but dinitrogen penta oxide is theoretical anhydride of nitric acid.2HNO3 = N2O5 + H2O==========No. From the Wikipedia article on nitrogen pentoxide:N2O5 was first reported by Deville in 1840, who prepared it by treating AgNO3 with Cl2.Therefore, nitrogen pentoxide is the anhydride of nitric acid.
The product of the reaction between anthracene and maleic anhydride is known as anthracene-maleic anhydride adduct. This adduct is commonly used in the synthesis of dyes, polymers, and other organic compounds.
Phthalic anhydride is slightly soluble in methanol. But beware! In this case, phthalic anhydride will actually react with its solvent. This is called estrification of the anhydride. Methanol will break the ring of Phthalic anhydride and make an ester. C6H4(CO)2O + CH3OH --> C6H4(CO2H)(CO2CH3) Similarly, you might THINK Phthalic anhydride is soluble in water, but it actually reacts with water to make phthalic acid. If you want to make a true solution of phthalic anhydride, I would recommend acetone, or methylethyl ketone.
If the excess acetic anhydride is not removed in the reaction vessel an unwanted reaction will occur. The acetic anhydride will react causing esterification.