Butane naming

Hernandez and Catlow (86) recently reported an investigation of n-butane and of n-hexane diffusion in silicalite the work is similar to that of June et al. (85). Many calculation details were the same as in the earlier work, including the assumption of identical Lennard-Jones coefficients of intermolecular dispersion and repulsion. Simulations were performed at different loadings for butane, namely, 2, 4, 5.3, and 8 molecules per unit cell. In addition, simulations were performed at a constant loading and variable temperature (200, 300, and 400 K) for both butane and hexane. These calculations were performed for 1000 ps, twice the length of those of June et al. The zeolite framework was held rigid. 

Calor gas, Calor propane The trade name for a liquified petroleum gas (LPG) sold in cylinders for domestic and industrial healing. Calor gas is the name used for commercial butane while commercial propane is sold as Calor propane. 

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... 

Two constitutionally isomeric alkanes have the molecular formula C4H10 One has an unbranched chain (CH3CH2CH2CH3) and is called n butane, the other has a branched chain [(CH3)3CH] and is called isobutane Both n butane and isobutane are common names... 

It IS hard to find a class of compounds in which the common names of its members have influenced organic nomenclature more than carboxylic acids Not only are the common names of carboxylic acids themselves abundant and widely used but the names of many other compounds are derived from them Benzene took its name from benzoic acid and propane from propionic acid not the other way around The name butane comes from butyric acid present m rancid butter The common names of most aldehydes are derived from the common names of carboxylic acids—valeraldehyde from valeric acid for exam pie Many carboxylic acids are better known by common names than by their systematic ones and the framers of the lUPAC rules have taken a liberal view toward accepting these common names as permissible alternatives to the systematic ones Table 19 1 lists both common and systematic names for a number of important carboxylic acids... 

Isopentane (Section 2 10) The common name for 2 methyl butane (CH3)2CHCH2CH3... 

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... 

Aldehydes. When the group —C(=0)H, usually written —CHO, is attached to carbon at one (or both) end(s) of a linear acyclic chain the name is formed by adding the suffix -al (or -dial) to the name of the hydrocarbon containing the same number of carbon atoms. Examples are butanal for CHjCHjCHjCHO and propanedial for, OHCCH CHO. 

Beginning with the fourth alkane, butane, we find we can draw a structural formula of a compound with four atoms and ten hydrogen atoms in two ways the first is as the normal butane exists and the second is as follows, with the name isobutane (refer to Table 1 for properties). 

In this manner, the four isomers of hexane are named 2-methyl pentane, 3-methyl pentane, 2,2,-dimethyl butane, and 2,3-dimethyl butane. 

In general, light ends towers are named after the light key. Thus, a depropanizer will take overhead the propane and lighter in the feed, and will have butane and heavier as the bottoms product. 

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. 

Alkanes are a class of saturated hydrocarbons with the general formula C H2n. -2- They contain no functional groups, are relatively inert, and can be either straight-chain (normal) or branched. Alkanes are named by a series of IUPAC rules of nomenclature. Compounds that have the same chemical formula but different structures are called isomers. More specifically, compounds such as butane and isobutane, which differ in their connections between atoms, are called constitutional isomers. 

SOLUTION (a) The longest chain contains four carbon atoms (butane). There are two CH3 (methyl) groups branching at the second carbon from the end of the chain (2). The correct name is... 

When molecules start to get complicated like this, they must be named carefully, according to some rules. One rule is to look for the longest unbranched alkane in the molecule. In this molecule, it is butane (four carbons). Next, describe the branch. In this case, it is methane (one carbon). Then describe where the branch is attached. In this case, it is attached to the second carbon in butane. The name is thus 2-methylbutane. 

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