Skip to main content
Select Source:

anhydride

anhydride (ănhī´drīd, –drĬd) [Gr.,=without water], chemical compound formed by removing water, H2O, from another compound; the anhydride can also react with water to form the original compound. An acid anhydride reacts with water to form an acid; e.g., sulfur trioxide, SO3, reacts with water to form sulfuric acid, H2SO4. A basic anhydride reacts with water to form a base; e.g., calcium oxide, CaO, reacts with water to form calcium hydroxide, Ca(OH)2. Anhydrides of organic acids have many uses. They react with alcohols to form esters; e.g., acetic anhydride, (CH3CO)2O, reacts with ethanol, C2H5OH, to form ethyl acetate, CH3COOC2H5, a useful solvent. They also react with ammonia and primary or secondary amines to form amides. Other important acid anhydrides include maleic anhydride and phthalic anhydride.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"anhydride." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. 17 Dec. 2018 <https://www.encyclopedia.com>.

"anhydride." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (December 17, 2018). https://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/anhydride

"anhydride." The Columbia Encyclopedia, 6th ed.. . Retrieved December 17, 2018 from Encyclopedia.com: https://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/anhydride

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

creatinine

creatinine Formed non‐enzymically from creatine (chemically the anhydride of creatine). Urinary excretion of creatinine is relatively constant from day to day, and reflects mainly the amount of muscle tissue in the body. Therefore the amounts of various components of urine are often expressed relative to creatinine.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"creatinine." A Dictionary of Food and Nutrition. . Encyclopedia.com. 17 Dec. 2018 <https://www.encyclopedia.com>.

"creatinine." A Dictionary of Food and Nutrition. . Encyclopedia.com. (December 17, 2018). https://www.encyclopedia.com/education/dictionaries-thesauruses-pictures-and-press-releases/creatinine

"creatinine." A Dictionary of Food and Nutrition. . Retrieved December 17, 2018 from Encyclopedia.com: https://www.encyclopedia.com/education/dictionaries-thesauruses-pictures-and-press-releases/creatinine

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.