Ethaneis a chemical compound with chemical formula C2H6, structural formula CH3-CH3.
It is an alkane, that is, an aliphatic hydrocarbon. At ordinary pressure and temperature ethane is a colourless, odourless gas; boiling point is ?88.6°; melting point is ?183.3°.
It is the simplest hydrocarbon containing more than one carbon atom. Ethane is a prominent compound of industrial importance, by converting it to ethylene or using it as a building block for the petrochemical industry, for the synthesis both of polyethylene plastic and other small compounds.
It is an alkane, that is, an aliphatic hydrocarbon. At ordinary pressure and temperature ethane is a colourless, odourless gas; boiling point is ?88.6°; melting point is ?183.3°.
It is the simplest hydrocarbon containing more than one carbon atom. Ethane is a prominent compound of industrial importance, by converting it to ethylene or using it as a building block for the petrochemical industry, for the synthesis both of polyethylene plastic and other small compounds.
General Description:
The hydrocarbon ethane consists of two carbons and six hydrogens. Classified as an alkane, or paraffin, hydrogen saturates the carbon atoms via covalent single bonds. Derived from the Latin term parum affinis, meaning “little affinity” for other compounds, paraffins are known for their stability and resistance to reactivity. Alkanes such as ethane are nonpolar, thus insoluble in polar solvents such as water.
Alkanes may be separated into fractions via distillation. The lowest boiling point (3-4 carbons) is used as fuel in cigarette lighters and barbecues. Gasoline follows in the next distillation fraction (5-11 Carbons), next kerosene and jet fuel (9-16 carbons), then diesel fuel (15-25 carbons), and the highest boiling point fractionation provides lubricants and greases (26+ carbons). The greater the branching of a hydrocarbon chain, the greater the stability of the molecule and the higher the boiling point. A colorless, odorless, nontoxic, yet flammable gas, ethane is a constituent of natural gas and petroleum (75% Methane, 25% Ethane, Propane, and Butane). These “fossil fuels” were formed through the decomposition of organic matter over thousands of years and today provide a major energy source. Large amounts of the element may also be located in the atmospheres of Saturn and Jupiter.
Alkanes may be separated into fractions via distillation. The lowest boiling point (3-4 carbons) is used as fuel in cigarette lighters and barbecues. Gasoline follows in the next distillation fraction (5-11 Carbons), next kerosene and jet fuel (9-16 carbons), then diesel fuel (15-25 carbons), and the highest boiling point fractionation provides lubricants and greases (26+ carbons). The greater the branching of a hydrocarbon chain, the greater the stability of the molecule and the higher the boiling point. A colorless, odorless, nontoxic, yet flammable gas, ethane is a constituent of natural gas and petroleum (75% Methane, 25% Ethane, Propane, and Butane). These “fossil fuels” were formed through the decomposition of organic matter over thousands of years and today provide a major energy source. Large amounts of the element may also be located in the atmospheres of Saturn and Jupiter.
A Model of the Ethane Molecule.-As is well known, ethane is a saturated hydrocarbon which contains eight valency electrons due to carbon and six due to hydrogen. Since it is saturated all the "possible electron positions" must be occupied by electrons. This can easily be accomplished in a cubic model by uniting the two carbon atoms by a double electron bond (two cubes having an edge in common). The union between the two carbon atoms being taken care of the next question to decide concerns the nature of the bond between the carbon and hydrogen atoms. It will be recalled that both diamond and graphite have adjacent atoms united by a single
electron bond (cube corner in common). Since this is the simplest type of atomic union and since there is no definite evidence in favor of any other type of bond between the carbon and hydrogen atoms in ethane this union will be assumed in this model as a first approximation. In
diamond the "electron position" uniting two adjacent atoms lies on the straight line connecting the nuclei. In graphite this is not the case.
electron bond (cube corner in common). Since this is the simplest type of atomic union and since there is no definite evidence in favor of any other type of bond between the carbon and hydrogen atoms in ethane this union will be assumed in this model as a first approximation. In
diamond the "electron position" uniting two adjacent atoms lies on the straight line connecting the nuclei. In graphite this is not the case.
Since the former bond is simpler from a geometrical standpoint it will be assumed for this model of ethane and, consequently, the radius of the carbon atom (half the body diagonal of the cube) will be taken as 0.77 A. And as a final approximation, it will be assumed that the "electron position" joining the hydrogen and carbon atoms is midway between the two nuclei.
It should be noted that these assumptions are arbitrary.
Their purpose is to enable us to set up a definite scale model of ethane which can be quantitatively tested by comparison with experiment. One of the most rigorous tests that such a model can undergo is to build it into a lattice structure and compare the diffraction effects computed from the model with those actually observed by means of X-ray analysis. As will be
shown in detail in another paper, the model herewith presented can be so arranged in a hexagonal close-packed lattice that it accounts quantitatively for all the observed diffraction effects, not only in regard to their position but also as to whether they are present or absent in the powder photographs. In this paper a description of this model is all that is intended.
shown in detail in another paper, the model herewith presented can be so arranged in a hexagonal close-packed lattice that it accounts quantitatively for all the observed diffraction effects, not only in regard to their position but also as to whether they are present or absent in the powder photographs. In this paper a description of this model is all that is intended.
No comments:
Post a Comment