Butane molecular formula

CHEMICAL NAME = butane MOLECULAR FORMULA = C4H10 MOLAR MASS = 58.1 g/mol COMPOSITION = C(82.66°/o) H( 17.34%)... 

Butane Molecular formula C4H10 a straight-chain hydrocarbon saturated, single bonds. 

Methane is the only alkane of molecular formula CH4 ethane the only one that is C2H6 and propane the only one that is C3Hj Beginning with C4H10 however constitutional isomers (Section 1 8) are possible two alkanes have this particular molecular formula In one called n butane, four carbons are joined m a continuous chain The nmn butane stands for normal and means that the carbon chain is unbranched The second isomer has a branched carbon chain and is called isobutane... 

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... 

The next hydrocarbon in the series is butane, another rather easily liquified gas used as a fuel. Together, butane and propane are known as the LP (liquified petroleum) gases. Butane s molecular formula is C4H,q, which is CHj bigger than propane. 

Isomers are substances having the same molecular formula and molecular weight, but differing in physical and chemical properties. Since branched and straight-chain alkanes with the same molecular formula can exist as distinct structures having different geometrical arrangement of the atoms, they are termed structural isomers. One example is C H,j (butane) which has two isomers ... 

Two different alkanes are known with the molecular formula C Hm- In one of these, called butane, the four carbon atoms are linked in a straight (unbranched) chain. In the other, called 2-methylpropane, there is a branched chain. The longest chain in the molecule contains three carbon atoms there is a CH3 branch from the central carbon atom. The geometries of these molecules are shown in Figure 22.2 (p. 581). The structures are... 

Compounds having the same molecular formula but different molecular structures are called structural isomers. Butane and 2-methylpropane are referred to as structural isomers of C4H10. They are two distinct compounds with their own characteristic physical and chemical properties. 

Isomers are distinctly different compounds, with different properties, that have the same molecular formula. In Section 22.1, we considered structural isomers of alkanes. You will recall that butane and 2-methylpropane have the same molecular formula, C4H10, but different structural formulas. In these, as in all structural isomers, the order in which the atoms are bonded to each other differs. 

Common Name n-Butane Synonym 1-butane Chemical Name n-butane CAS Registry No 106-97-8 Molecular Formula C4H10 Molecular Weight 58.122 Melting Point (°C) ... 

Figure 11.19 Two structural isomers having the molecular formula C4Hi0. (a) butane, (b) 2-methylpropane.

The conversion of a chemical with a given molecular formula to another compound with the same molecular formula but a different molecular structure, such as from a straight-chain to a branched-chain hydrocarbon or an alicyclic to an aromatic hydrocarbon. Examples include the isomerization of ethylene oxide to acetaldehyde (both C2H40) and butane to isobutane (both C4H10). 

The molecular formulas just shown for 10 alkane hydrocarbon molecules represent the proportions of carbon to hydrogen in each molecule. These formulas do not reveal much about their structures, but rather indicate the proportions of each element in their molecules. Each molecule may have several different structures while still having the same formula. Molecules with different structures but the same formulas are called isomers. For example, n-butane is formed in a straight chain, but in an isomer of butane, the CH branches off in the middle of the straight chain. Another example is ethane, whose isomeric structure can be depicted as H,C H,C-CH,. The name for the normal structure sometimes uses n in front of the name. 

For a given molecular formula there is often more than one way of joining the atoms together, whilst still satisfying the rules of valency. Such variants are called structural isomers or constitutional isomers - compounds with the same molecular formula but with a different arrangement of atoms. A simple example is provided by C4H10, which can be accommodated either by the straight-chained butane, or by the branched-chain isobutane (2-methylpropane). 

This second branched molecule is called isobutane. Compounds sharing the same molecular formula but having different structures are called structural isomers. Normal butane and isobutane have different physical properties. The number of structural isomers for the alkanes is included in Table 15.1. It can be seen in this table that as the number of carbon atoms increases that the number of possible isomers also increases. The fact that numerous isomers exist for most organic compounds is another reason why there are so many organic compounds. 

Molecular formulas merely include the kinds of atoms and the number of each in a molecule (as C4H , for butane). Structural formulas show the arrangement of atoms in a molecule (see Fig. 1-1). When unshared electrons are included, the latter are called Lewis (electron-dot) structures [see Fig. 1-1(/)]. Covalences of the common elements—the numbers of covalent bonds they usually form—are given in Table 1-1 these help us to write Lewis structures. Multicovalent elements such as C, O. and N may have multiple bonds, as shown in Table 1-2. In condensed structural formulas all H s and branched groups are written immediately after the C atom to which they are attached. Thus the condensed formula for isobutane [Fig. l-l(f>)) is CH,CH(CH,)... 

Organic compounds show a widespread occurrence of isomers, which are compounds having the same molecular formula but different structural formulas, and therefore possessing different properties. This phenomenon of isomerism is exemplified by isobutane and -butane [Fig. l-l(a) and (b)]. The number of isomers increases as the number of atoms in the organic molecule increases. 

When two different compounds have the same molecular formula but differ in the nature or sequence of bonding, they are called constitutional isomers. For example, ethanol and dimethylether have same molecular formula, C2HgO, but they differ in the sequence of bonding. Similarly, butane and isobutane are two constitutional isomers. Constitutional isomers generally have different physical and chemical properties. 

More than one stable substance can correspond to a given molecular formula. Examples are butane and 2-methylpropane (isobutane), each of which has the molecular formula C4H10. Similarly, methoxymethane (dimethyl ether) and ethanol have the same formula, C2H60 ... 

Only two alkanes have the molecular formula C4H10 butane and isobutane (2-methylpropane)— both of which give two monochlorides on free-radical chlorination. However, dehydrochlorination of one of the monochlorides derived from butane yields a mixture of alkenes. 

Alkanes having a particular molecular formula can exist as different constitutional isomers. For example, the alkane having the molecular formula C4H10can exist as two constitutional isomers-the straight chain alkane (butane) or the branched alkane (2-methylpropane Following fig.). These are different compounds with different physical and chemical properties. 

Thus, while a molecular formula tells the number and type of atoms present in a compound, it tells nothing about the structure. The structural formula is a two-dimensional representation of a molecule and shows the sequence in which the atoms are connected and the bond type. For example, the molecular formula, C4H10, can be represented by two different structures butane (4) and 2-methylpropane (isobutane) (5). 

One difficulty that branches present is the possibility of the formation of isomers, molecules that have the same molecular formula but different structures. In Figure 19.2, note how the molecules butane and 2-methylpropane have the same molecular formulas but different structures and properties ... 

In the previous section, we mentioned that different molecules, isomers, can have the same molecular formula but have a different structure. We saw that butane, C4H10, has two isomers—butane (also known as n-butane) and 2-methylpropane. As molecules get longer, more and more isomers become possible. In the first sample, we will consider the number of isomers of pentane. 

These two compounds are isomers because they are different compounds with different properties, yet they have the same molecular formula. They are constitutional isomers because their atoms are connected differently. The first compound (n-butane for normal butane) has its carbon atoms in a straight chain four carbons long. The second compound ( isobutane for an isomer of butane ) has a branched structure with a longest chain of three carbon atoms and a methyl side chain. 

Although we have derived the CnH2n+2 formula using the unbranched n-alkanes, it applies to branched alkanes as well. Any isomer of one of these n-alkanes has the same molecular formula. Just as butane and pentane follow the C H2 +2 rule, their branched isomers isobutane, isopentane, and neopentane also follow the rule. 

Butane is the four-carbon alkane, with molecular formula C4H10. We refer to n-butane as... 

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