Molecules containing two carbon atoms

Using a fixed photon energy (21.22 eV), the breakdown curve has been obtained for HF loss from the vinyl fluoride ion and a rate coefficient, k(E), has been derived [211, 784]. 

Breakdown diagrams determined by threshold PIPECO have been reported for C2H4 and C2D4 [804] and C2F6 [446], C2H2 [270, 877], 

C2H4 [877], C2H6 [877], C2H5OH [130], (CH3)2Hg [154] and C2F6 [766, 767, 768, 769] have been studied at fixed wavelength. Decompositions of (C2F6)f have been shown to be non-statistical in that electronic energy is not randomised (see Sect. 8.2). 

Ketene [798], cis- and frans-difluorethylene [785] and ethyl iodide [18] have also been studied by PIPECO (see Sect. 8). 

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SAMPLE SOLUTION (a) The molecule contains two carbon atoms, which are bonded to each other. Both carbons bear two hydrogens. One carbon bears the group HO— the other is attached to —NH2. 

The empirical formula of a compound can be established by evaluating the intensities of isotope peaks M + l, M + 2, etc Relative to the parent peak. Isotope peaks arise because of the natural abundance of certain heavier isotopes in some molecules of the sample. Thus a compound containing a single carbon atom will produce anM + 1 peak 1.08% of the intensity of the parent peak because 1.08% of the molecules contain a, 3C atom. If the molecule contains two carbon atoms the M + l peak will be 2.16% of the parent peak and an M + 2 peak due to molect)le containing two, JC atoms will bfc produced of relative intensity 0.01 %. Table 9.10 lists the principal... 

Ethyne is a neutral molecule, containing two carbon atoms that are treated separately. 

The number of each atom in the compound is indicated by a subscript to the right of the atomic symbol. For example, tbe chemical formula of ethylene, C2H4, tells us that each molecule contains two carbon atoms and four hydrogen atoms. 

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... 

When a candle is burned, a gas is produced—a gas containing carbon dioxide and water vapor. It is useful to describe such a gas as a collection of molecules, each molecule containing smaller units called atoms. Each carbon dioxide molecule contains one carbon atom and two oxygen atoms. Each water molecule contains one oxygen atom and two hydrogen atoms. Where did these atoms come from Were they present in the candle before it burned ... 

The variation in polymer structures is observed when the backone of the polymer molecule contains a carbon atom attached to two different side groups. Such polymers can have different configurational arrangements or tacticity. 

Teflon is the brand name for the chemical compound called polytetrafluoroethylene (PTFE). One molecule of PTFE contains two carbon atoms bonded to four fluorine atoms. Many molecules of PTEE can form polymer chains known as fluoropolymers. 

A carbonium ion is defined by this theory as a molecule containing a carbon atom which is deficient two electrons in its outer shell, and consequently carries a positive charge. The carbonium ion is highly reactive, and can undergo several transformations and reactions, among which are the following ... 

For instance, carbon has two naturally occurring isotopes, with a natural abundance of 99.89% and C with a natural abundance of 1.11%, so that roughly one in every 100 carbon atoms will be a C. In a molecule containing 10 carbon atoms there are 10 chances of finding a atom, which adds up to a 1 in 10 chance that this particular molecule will contain one C, so that for a Cjo molecule we should see a peak corresponding to M + 1 with an intensity of 1/10 of that of the molecular ion. For small to medium sized molecules i.e. < 100 carbons) the most abundant peak is the one corresponding to exclusively C atoms ... 

If the molecule contains two carbon centers that have four different substituents attached but are arranged such that they are mirror images of one another within the molecule, the molecule will not be optically active. Such an example is shown below in general for a 1,2-X-1,2-Y-1,2-Z substituted ethane. Many other examples are possible, the only criterion being that the carbon atoms that have four substituents must have a mirror image carbon center within the molecule. 

Ether. A molecule containing two carbons linked by an oxygen atom. 

Cyclic (or ringed) hydrocarbons are simply named with the prefix cyc/o- followed by an ending that is determined by how many carbon atoms are in the molecule. For example, a ringed hydrocarbon molecule containing five carbon atoms and only single bonds would be named cyclopentane. If the same molecule had a double bond between two carbon atoms in the ring, the name would be cyclopentene. 

Each element has a specific symbol that is different from the symbol for any other element. In a chemical formula, the symbol stands for an atom of an element. Molecular substances are composed of two or more atoms that are tightly bound together. The formula for a molecular substance consists of the symbols for the atoms that are found in that molecule. For instance, the formula for carbon dioxide is CO2. Note the use of the subscript to show that each molecule contains two oxygen atoms in addition to the one carbon atom. Also note that the 1 for the one carbon atom is not written. The molecular mass of CO2 is the sum of the atomic mass of carbon plus twice the atomic mass of oxygen and is expressed in u. As was discussed directly above, the molar mass of CO2 is the mass in grams equal to the molecular mass in u. A mole of carbon dioxide is 12.0 u + 2(16.0 u) = 44 u. This result can be expressed as 44 g to indicate one Avogadro s number, Na, of CO2 molecules. Recall that Na is 6.0221 x 1023 things—molecules in this case. 

Chemical Formula A scientific notation that identifies the number of atoms in one molecule of a compound. It is written with element symbols and the numbers of atoms in subscript. The formula for carbon dioxide is C02. One molecule contains one carbon atom and two oxygen atoms. 

Because each water molecule contains two hydrogen atoms, it is necessary to multiply the number of moles of water by 2 to find the number of moles of hydrogen atoms. Having found that the compound contains equal numbers of moles of carbon and hydrogen, we have determined that its empirical formula is CH. Its molecular formula may be CH,... 

B. ethene]—If you try to sketch the structural formula for C2H4, you will see that you will need a double bond between the two carbon atoms, in order to occupy all of the bonding electrons. We use the prefix eth because each molecule has two carbon atoms, and the suffix ene because it contains a double bond. 

To picture what polymers are, it is helpful to start with small synthetic polymers. You use such polymers every day. Plastics, synthetic fabrics, and nonstick surfaces on cookware are polymers. The unsaturated hydrocarbon ethylene, C2H4, is the monomer of a common polymer used often in plastic bags. The monomers are bonded together in a chemical reaction called polymerization (puh lih muh ruh ZAY shun). As you can see in Figure 15, the double bond breaks in each ethylene molecule. The two carbon atoms then form new bonds with carbon atoms in other ethylene molecules. This process is repeated many times and results in a much larger molecule called polyethylene. A polyethylene molecule can contain 10,000 ethylene units. 

The simplest alcohol is methanol, CH, ( )I I. also called methyl alcohol. Ethanol, CHjCH OH, also known as ethyl alcohol, is the next simplest, containing two carbon atoms. When the number of carbon atoms in an alcohol molecule is greater than two several isomers are possible, depending on the location of the -OH group as well as on the nature of the carbon chain. 

The symbol for an element is used to designate that element as distinct from other elements. In a formula the symbol designates an atom of the element. Molecular substances consist of independent molecules in each of which two or more atoms are tightly bound together. The formula for a molecular substance consists of the symbols for the atoms in one molecule. For instance, the formula for carbon dioxide is CO2. Note the use of the subscript, 2, to show that each molecule contains two oxygen atoms... 

The molecule contains a carbon atom, two chlorine atoms, and two fluorine atoms. There are two covalent C-Cl bonds and two covalent C-F bonds. The Cl and F atoms have three lone pairs each. 

The formation of ketones is explained by the occurrence of ketom zation reaction of two carboxylic acid molecules. The ketone molecule contains one carbon atom less than the two acid molecules, and the position of the ketone function is determined by the size of the alkyl chains and R2 ... 

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