Molecular formula expanded

Using Expanded Molecular Formulas to Represent Hydrocarbons... 

Propane s expanded molecular formula is CH3CH2CH3. As you can see from this formula, the expanded molecular formula gives a clearer idea of atomic arrangement. It implies that a CH3 group is attached to a CH2 group, which is attached to another CH3 group. 

Expanded molecular formulas for five structural arrangements of CeH ... 

The expanded molecular formulas of C6Hi4 give you a better idea of the arrangement of the carbon and hydrogen atoms in its five possible isomers. You can use other methods as well, however, to represent hydrocarbons and other organic compounds. These methods are outlined below. 

C6H14 can have any one of these five structural arrangements. How do the ball-and-stick models compare with the expanded molecular formulas for C6H14 How does each isomer differ from the rest ... 

Q O You have seen the expanded molecular formulas and condensed structural diagrams for the five isomers of C6Hi4. Draw the complete and line structural diagrams for each of these isomers. 

Name Number of carbon atoms Expanded molecular formula... 

Before proceeding further, it is necessary to learn different ways of drawing the structure of organic compounds. To see how atoms are connected in 2-methylbutane (C5H12), for example, we must first write the expanded molecular formula, CH3CH(CH3)CH2CH3 and draw its structural formula, shown in Figure 16.3(a). 

Mole-mass, 55,70-72q Molecular formula A formula in which the number of atoms of each type in a molecule is indicated as a subscript after the symbol of the atom, 34,59-60 Molecular geometry The shape of a molecule, describing the relative positions of atoms, 175 193q electron pairs, 179t major features, 175-176 molecules with expanded octets, 181t molecules with unshared electron pairs, 181t... 

Recent advances in instrumentation and ionization techniques are described briefly. Several sections have been rewritten and expanded for greater clarity. The useful Table of Formula Masses (four decimal places) has been shortened by eliminating entries that are unlikely in the present context. The Table is convenient for selecting tentative molecular formulas and fragments on the basis of unit-mass peaks. Given high-resolution peaks, specific molecular or fragment formulas can be selected. 

This third edition contains nearly 9000 chemical incompatibility profiles and nearly 250 new entries. Rather than simply revise the second edition, the authors chose to rewrite and expand all of the chemical profiles. At the suggestion of reviewers of the proposal for the third edition, some foreign language names have been eliminated to make room for new entries. In addition to more flash points, the following were added molecular formulas, lower and upper explosive limits, autoignition tenqieratures, and NFPA -type (Red)... 

A stepwise process is used to convert a molecular formula into a Lewis structure, a two-dimensional representation of a molecule (or ion) that shows the relative placement of atoms and distribution of valence electrons among bonding and lone pairs. When two or more Lewis structures can be drawn for the same relative placement of atoms, the actual structure is a hybrid of those resonance forms. Formal charges are often useful for determining the most important contributor to the hybrid. Electron-deficient molecules (central Be or B) and odd-electron species (free radicals) have less than an octet around the central atom but often attain an octet in reactions. In a molecule (or ion) with a central atom from Period 3 or higher, the atom can hold more than eight electrons by using d orbitals to expand its valence shell. 

Okaramine Q (18) had a molecular formula of C32H32N4O4. The UV spectrum (Xmax 234, 288, 376 nm) indicated the presence of an indole chromophore with an expanded conjugation. The H-NMR spectrum of 18 resembled that of okaramine B (2), except for the absence of the methoxyl proton signal in 2 and the presence of signals due to isolated methylene protons. A precise comparison between the NMR spectra of 18 and 2 led to the conclusion that 18 is a demethoxyl derivative of 2 [23]. 

Butyl acetate (BYOO-til AS-uh-tate) exists in three isomeric forms. Isomers are two or more forms of a chemical compound with the same molecular formula, but different structural formulas and different chemical and physical properties. Their names and synonyms are as follows n-butyl acetate is known as butyl ester, or butyl ethanoate -butyl acetate is called i-methylpropyl ester and acetic acid -butyl ester and ferf-butyl acetate is known by 1,1,-dimethylethyl ester or acetic acid, ferf-butyl ester. The expanded chemical formulas for the forms are slightly different n-butyl acetate, CH3C00CH2CH2CH2CH3 -butyl acetate, CH3COOCH(CH3)(C2H5) and ferf-butyl acetate, CH3C00C(CH3)3. 

Radialenes (49) are a homologous series of all-eA o-methylenecycloalkanes of molecular formula C H (Fig. 13-3) [60], Upon insertion of butadiynyl moieties into the cyclic framework between each pair of vicinal ejto-methylene units, the carbon-rich expanded radialenes 50 (C3 H ) are obtained. Starting from suitable protected tetraethynylethenes, the perethynylated expanded radialenes 51-53 were prepared via 54, as shown in Scheme 13-11 [41], They possess large carbon cores with silyl-protected peripheral valences and can be viewed as C40 + 8 (/Pr)3Si (51), Cjo + 10 (iPr)3Si (52), and C , + 12 (/Pr)3Si (53). The diameters of these large carbon-rich molecules are in the nanometer range with values of = 17 A (for 51), 19 A (for 52), and 22 A (for 53). 

Identify each of the following as a condensed structural formula, expanded structural formula, or molecular formula ... 

With this in mind, let s expand our shills set. Let s explore how to calculate the HDI when other elements are present in the molecular formula. 

Expand the bond-line formulas of the amino acid cysteine and the neurotransmitter serotonin to show all the unshared electron pairs. Molecular formulas of organic compounds are customarily presented in the fashion CaMbX Yd- Carbon and hydrogen are cited first, followed by the other atoms in alphabetical order. What are the molecular formulas of cysteine and serotonin ... 

Expand the following structural representations so as to more clearly show all the atoms and any unshared electron pairs. What are their molecular formulas Are any of them isomers ... 

One way to approach this kind of problem is to identify whatever structural features you can from the NMR spectrum and then use the information from the molecular formula and the IR spectrum to expand on that knowledge. 

A hexane molecule can be represented in several ways molecular formula, ball-and-stick model, expanded structural formula, condensed structural formula, and skeletal formula. 

The smaller alkanes from 1-4 carbon atoms are gases at room temperature and used as heating fuels. The alkanes with 5-8 carbon atoms are liquids at room temperature and found in fuels such as gasoline. The molecular formula gives the total number of each kind of atom, but does not indicate the arrangement of the atoms in the molecule. Table 17.2 shows the molecular, expanded, and condensed structural formulas for alkanes with one, two, and three carbon atoms. 

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