Page:Encyclopædia Britannica, Ninth Edition, v. 5.djvu/565

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ABC—XYZ

FAMILIES OF COMPOUNDS.] CHEMISTKY 553 salts of the fatty body acetic acid, when it is heated with sulphuric acid, loses water and is transformed into mesitylene or trimethylbenzene : 3CO(CH 3 ) 2 - 3OH 2 = C 6 H 3 (CH 3 ) 3 . Acetone. Water. Trimethylbenzene. Families of Organic Compounds. Most of the organic compounds at present known can be referred to certain families which we shall now proceed to enumerate. I. Hydrocarbons. These are the parent bodies from which the remaining families are derived. Their arrange ment into homologous and isologous series has already been discussed. IT. Alcohols. Formed from hydrocarbons by the sub stitution of hydroxyl for hydrogen : CH 4 , CH 3 OH ; C 2 H 6 , C 2 H 5 OH , C H 4 "(OH) 2 ; Methane. Methyl alcohol Ethane. Ethyl alcohol. Ethene alcohol. C 3 H S , C 3 H 7 OH , C 2 H 6 "(OH) 2 , C 3 H 5 "(OH) 3 . Propane. Propyl alcohol. Propene alcohol" Propenyl alcohol. III. Haloid Ethers. Formed from hydrocarbons by the substitution of halogen elements for hydrogen : CjjHg Propane. C 3 H 7 C1 Propyl chloride. L/ 3 H.g -t>r. 7 , O 3 -tie 1 3 . Propene dibromide. Propenyl triiodide. IV. Ethers. Derived from alcohols by the substitution of oxygen for hydroxyl ; thus, from 2(C 2 H 5 OH) , Ethyl alcohol we have (C 2 H 5 ) 2 Ethyl oxide or ether. C 2 H 4 "(OH) 2 , Ethene alcohol C 2 H 4 "0 Ethene oxide. C 3 H 5 "(OH) 3 Propenyl alcohol. (C 3 H 5 ) 2 O 3 . Propenyl oxide. V. Sulphur, Selenium, and Tellurium Alcohols and Ethers. These compounds are the analogues of the alcohols and ethers, oxygen being replaced by sulphur, etc. The thio-alcohols are known as mercaptans : C 2 H 5 OH , C 2 H 5 SH , C 2 H 5 SeH , (C 2 H 5 ) 2 S , (C 2 H 6 ) 2 Te; Ethyl sulphy- Ethyl selenio- P . . _ Ethyl alcohol diate or hydrate or selenium , V/ mercaptan. mercaptan. sulphide. telluride. C 2 H/(OH) 2 , C 2 H 4 "(SH) 2 ; C 3 H 5 " (OH) 3 , C 3 H 5 "(SH) 3 . Ethene alcohol. Ethene sulphydrate. Propenyl alcohol. Propenyl sulphydrate. YI. Aldehydes. Derived from hydrocarbons by the replacement of hydrogen by the radicle (COH) : CH 4 Methane. CH 3 .COH Acetic aldehvde. "VII. Ketones. Derived ment of hydrogen in the carbon radicles : CH 3 .COH , CH 3 .CO.CH 3 Acetic aldehyde. Dimethyl-ketone. VIII. Organic Acids. garded as hydrocarbons in carboxyl :

C 2 H 6 , C 2 H 5 .COH .

Ethane. Propionic aldehyde. from aldehydes by the replace- COH group by monad hydro-

C 2 H 5 .COH , C 2 H 5 .CO.CH 3 .

Propionic aldehyde. Ethyl-methyl ketone. These compounds may be re- which hydrogen is replaced by CH 4 , CH 3 .COOH ; C H 6 , C 2 H 4 ".(COOH), . Methane. Acetic acid. Ethane. Succinic acid. The organic acids may likewise be regarded as derived from alcohols by the replacement of H 2 by O : CH 3 .CH 2 .OH Ethyl alcohol. CH 3 .CO.OH Acetic acid. F , C 2 0/(OH) 2 . Ethene alcohol. GlycoLlic acid. Oxalic acid. Corresponding thio-acids are known thus : C 2 H 3 O.OH C 2 H 3 O.SH Acetic acid. Thiacetic acid. ^ IX. Anhydrides. Derived from acids by the substitu tion of oxygen for hydroxyl, and thus bearing the same relationship to the acids that the ethers bear to the alco hols ; thus, from 2(CH 3 .CO.OH) , C 2 H/C 2 2 (OH) 2 , 2(C 6 H 5 .CO.OH) Acetic acid. Succinic acid. Benzoic acid. we have (CH 3 .CO) 2 , C 2 H/.C 2 2 .0 , (C 6 H 5 .CO) 2 0. Acetic anhydride. Succinic anhydride. Benzoic anhydride Corresponding thio-compounds are capable of existing : (CH 3 .CO) 2 S = thiacetic anhydride. X. Acid Halides. Derived from acids by the substitu tion of halogen elements for hydroxyl. These compounds are thus most conveniently formulated as compounds of an oxygenated or acid radicle 1 with the halogens : C 2 H 3 O.C1 , (C 2 H 3 0) 3 I " ; Acetyl chloride. Acetyl iodide. j C 4 H 4 O 2 .C1 2 . Succinyl chloride. XI. Ethereal Salts or Compound Ethers. Derived from acids, organic or inorganic, by the substitution of a hydro carbon radicle for the hydrogen of the hydroxyl : N0 2 .OH , N0 2 .0(C 2 H 5 ) ; Nitric acid. Ethyl nitrate. S0 2 .(OH) 2 , S0 2 .OH.(OC 2 H.) , S0 2 .(OC 2 H 5 )., Sulphuric acid. Ethyl-hydrogen sulphate. Diethyl sulphatet PO.(OH) 3 , PO.(OH) 2 (OC 2 H 5 ) , PO.(OC 2 H 5 ) 3 ; Phosphoric acid. Monethyl phosphate. Triethyl phosphate. C 2 H 3 O.HO Acetic acid. C 4 H 4 0/.(OH) 2 Succinic acid. C 2 H 3 O.OH Acetic acid. C 2 H 3 0.(OC 9 H 5 ) . Ethyl acetate C 2 H 3 0.(SC 2 H 5 ) . Ethyl thiacetate The thio-acids also form ethereal salts : C 2 H 3 O.SH Thiacetic acid. XII. Organo-metallic Bodies. Compounds of hydro carbon radicles with rnetals : NaC 2 H 5 ; Zn(C 2 H 3 ) 2 ; Sn(C 2 H 5 ) 4 ; SnI 2 (C 2 H 5 ) 2 . Sodium ethide. Zinc ethide. Stannic ethide. Stannic diiodo- diethide. XIII. Amines or Compound Ammonias. These com pounds are most conveniently regarded as derivatives of ammonia and its hydrate, and of ammonium haloid salts, hydrogen being replaced by hydrocarbon radicles : ( C H H ( C,IL ( fLH. ( n fT- i H 2 * H H If

  • .<H

I ** Ammonia. Ethylamine. Triethylamine. Eth ^ yl - Ethene diamine. N C 2 H 5 NJCA [0& Tetrethyl- ammonium hydrate. These compounds may likewise be formulated as hydro carbon derivatives : Ethane Ammonium Ethylammonium Tetrethyl-ammo- Methyl carb- chloride. chloride. nium iodide. aniine. Methane. or amido- methane. Ethylamine or Ethene diamine or amido-ethane. diamido-ethane. C 6 H 6 , C 6 H 5 (NH 2 ) , C G H/(NH 2 ) 2 , C 6 H/ (NH 2 ) 3 . Benzene. Amidobenzene. Diamidobenrene. Triamidobenzene. The phosphorus, arsenic, antimony, and bismuth ana logues of ammonia yield derivatives corresponding to the amines : 1 The names of all acid radicles, perissad and artiad (i.e., odd and even), end in yl.

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