Ethanal, naming

The cross over point of the free energy curves of heptane and ethylene occur at a lower temperature than that of ethane, namely at about 800K. Pyrolysis of naphtha to ethylene can therefore be practiced at lower temperatures than that required for the pyrolysis of ethane. 

The steam pyrolysis of LPG follows the same pathway of that for ethane, namely by a complex branching chain free radical mechanism. This can be divided into initiation, chain propagation and chain termination reactions. This gives rise to a large number of intermediates and products. As with ethane, products of higher carbon number than the feed are formed. 

The first line of the header block contains the molectrle name and does not require any particular format (a rare case). If no name is available the line is blank. For ethanal two names are specified its identifier within the NCI database (NSC 7594) and the regular name. 

The lUPAC rules assign names to unbranched alkanes as shown m Table 2 2 Methane ethane propane and butane are retained for CH4 CH3CH3 CH3CH2CH3 and CH3CH2CH2CH3 respectively Thereafter the number of carbon atoms m the chain is specified by a Latin or Greek prefix preceding the suffix ane which identifies the com pound as a member of the alkane family Notice that the prefix n is not part of the lUPAC system The lUPAC name for CH3CH2CH2CH3 is butane not n butane... 

Alkanes. The saturated open-chain (acyclic) hydrocarbons (C H2 +2) have names ending in -ane. The first four members have the trivial names methane (CH4), ethane (CH3CH3 or C2H5), propane (C3H8), and butane (C4Hjo). For the remainder of the alkanes, the first portion of the name... 

The prefix thioxo- is used for naming =S in a thioketone. Sulfur analogs of acetals are named as alkylthio- or arylthio-. For example, CH3CH(SCH3)OCH3 is l-methoxy-l-(methylthio)ethane. Prefix forms for -carbothioic acids are hydroxy(thiocarbonyl)- when referring to the O-substituted acid and mercapto(carbonyl)- for the S-substituted acid. 

Acetaldehyde [75-07-0] (ethanal), CH CHO, was first prepared by Scheele ia 1774, by the action of manganese dioxide [1313-13-9] and sulfuric acid [7664-93-9] on ethanol [64-17-5]. The stmcture of acetaldehyde was estabhshed in 1835 by Liebig from a pure sample prepared by oxidising ethyl alcohol with chromic acid. Liebig named the compound "aldehyde" from the Latin words translated as al(cohol) dehyd(rogenated). The formation of acetaldehyde by the addition of water [7732-18-5] to acetylene [74-86-2] was observed by Kutscherow] in 1881. 

Tetrachloroethylene [127-18-4] perchloroethylene, CCl2=CCl2, is commonly referred to as "perc" and sold under a variety of trade names. It is the most stable of the chloriaated ethylenes and ethanes, having no flash poiat and requiring only minor amounts of stabilizers. These two properties combiaed with its excellent solvent properties account for its dominant use ia the dry-cleaning iadustry as well as its appHcation ia metal cleaning and vapor degreasiag. 

Oxydehydrogenation. Because of the limitations of ethane dehydrogenation equihbrium, research has focused on ways to remove one of the products, namely hydrogen, by chemical methods. In this way, hydrogen is oxidized to water and there is no equihbrium limitation. 

The reaction shown above for the steam reforming of methatie led to die formation of a mixture of CO and H2, die so-called synthesis gas. The mixture was given this name since it can be used for the preparation of a large number of organic species with the use of an appropriate catalyst. The simplest example of this is the coupling reaction in which medrane is converted to ethane. The process occurs by the dissociative adsorption of methane on the catalyst, followed by the coupling of two methyl radicals to form ethane, which is then desorbed into the gas phase. 

An analogous series of hydrocarbons, and one of the simplest, are the compounds known as the alkanes. In this series, the names of all the compounds end in -ane. The first compound in this series is methane. Methane s molecular formula is CH. Methane is a gas and is the principal ingredient in the mixture of gases known as natural gas. The next compound is this series is ethane, whose molecular formula is CjHj. It is also a gas present in natural gas, although in a much lower percentage than methane. The difference in the molecular formulas of methane and ethane is one carbon and two hydrogen atoms. 

Chemical Name N-[(4-Methoxyphenyl)methyl] -N,N -dimethyl-N-2-pyrimidinyl-1,2-ethane-diamine monohydrochloride... 

In refrigerating systems, halogen derivatives of methane and ethane marketed under the trade names of Arctons and Freons are without action on pure aluminium and its copper-free alloys in dry conditions, but in wet conditions monochlorodi-, dichloromono-and trichloromonofluoromethanes can hydrolyse to produce slight attack on the aluminium. 

Straight-chain alkanes are named according to the number of carbon atoms they contain, as shown in Table 3.3. With the exception of the first four compounds—methane, ethane, propane, and butane—whose names have historical roots, the alkanes are named based on Greek numbers. The suffix -one is added to the end of each name to indicate that the molecule identified is an alkane. Thus, pentane is the five-carbon alkane, hexeme is the six-carbon alkane, and so on. We ll soon see that these alkane names form the basis for naming all other organic compounds, so at least the first ten should be memorized. 

For historical reasons, there are a few alkenes whose names are firmly entrenched in common usage blit don t conform to the rules. For example, the alkene derived from ethane should be called etheite, but the name ethylene has... 

The name ethyl is derived from the name of the parent hydrocarbon, ethane. In the same way the name of the methyl group (CH3—) is derived from that of methane, CH4 the name of the propyl group (CH3CH2CH2—) is derived from propane, CH3CH2CH3 etc. 

Detailed measurements of the solubility between the lower and upper critical end points have been made only for the solutions in ethylene of naphthalene,14 hexachlorethane,30 and />-iodochloro-benzene.21 Atack and Schneider2 have used dilute solutions of the last-named substance to study the formation of clusters near the gas-liquid critical point of ethane. 

To name an alkane in which the carbon atoms form a single chain, we combine a prefix denoting the number of carbon atoms with the suffix -ane (Table 18.1). For example, CH,—CH, (more simply, CH,CH,) is ethane and CH,—CH2—CH, (that is, CH,CH2CH,) is propane. Cyclopropane, C,H6 (15), and cyclohexane, C6H12 (16), are cycloalkanes, alkanes that contain rings of carbon atoms. 

In ethane it was possible to consider the C-H distance as a parameter and to evaluate it as 1.09 0.03 A. In the case of the other hydrocarbons studied in this investigation (aside from ethylene) there are so many structural parameters that the experimental evaluation of the C-H distance cannot be carried out conveniently. We have accordingly assumed values for this distance in these substances, namely, C-H = 1.09 A. for a carbon atom which forms four single bonds to... 

Note 1. The alternative name using a substituent prefix (see 2-Carb-35.1) is 4-0-acetyl-3-amino-2,3,6-trideoxy-l-0,3-N-(ethan-l-yl-l-ylidene)-3-C-methyl-a-L-rifco-hexopyranose... 

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