Flammable gases alkanes

C3Hg) compare with alkane and hydrocarbon. A colourless, odourless, flammable gas, found in petroleum and natural gas. It is used as a fuel and as a raw material for building more complex organic molecules. Propane is the third member of the alkane series. 

Ethane - An alkane (saturated aliphatic hydrocarbon) with two carbon atoms, CH3CH3. A colorless, odorless, flammable gas. Relatively inactive chemically. Obtained from natural gas. Used in petrochemical synthesis and as fuel. 

Alkanes are widespread both on Earth and on other planets. The atmospheres of Jupiter, Saturn, Uranus, and Neptune contain large quantities of methane (CH4), the smallest alkane, which is an odorless and flammable gas. In fact, the blue colors of Uranus and Neptune are due to methane in their atmospheres. Alkanes on Earth are found in natural gas and petroleum, which are formed by the decomposition of plant and animal material that has been buried for long periods in the Earl s crust, an environment with little oxygen. Natural gas and petroleum, therefore, are known as fossil fuels. 

EXPLOSION and FIRE CONCERNS flammable gas NFPA rating Health 3, Flammability 4, Reactivity 3 volatile flammable liquid below room temperature polymerizes violently on contact with ammonia, alkali hydroxides, amines, metallic potassium, acids, aluminum chloride, iron (III) chloride, tin (IV) chloride, aluminum oxide, iron oxide, and rust reacts explosively with glycerol at 200°C vapor forms explosive mixtures with air vapors may travel to an Ignition source and flash back incompatible with bases, alcohols, air, copper, trimethyl amine, magnesium perchlorate, mercaptans, alkane thiols, bromoethane, and others explosive decomposition may occur in vapor or liquid phases use water spray, dry chemical, foam, or carbon dioxide for firefighting purposes. 

CHEMICAL PROPERTIES stable under ordinary conditions of use and storage undergoes acid-catalyzed hydration to yield ketones completely hydrogenated in the presence of metal hydrogenation catalysts (e.g., Pt, Pd, Ni, or Rh), yielding alkanes reacts with hydrogen halides to give alkenyl halides produces carboxylic acids when subjected to ozonolysis FP (flammable gas) LFL/UFL (1.7%, unknown) AT (unknown) HF (184.9 kJ/mol gas at 25°C). 

Description and general properties. Methane [74-82-8], also called marsh gas, with the chemical formula CH, the relative molar mass of 16.04276 and a low density of 0.7168 kg.m under normal temperature and pressure conditions (273.15 K and 101.325 kPa), is the first and lightests member of the alkanes (i.e., saturated hydrocarbons or olefins with chemical formula C H2 2)- Methane is a colorless, odorless, non-poisonous and flammable gas that solidifies at -182.4°C (90.75 K) and boils under atmospheric pressure at -161.5°C (111.65 K). Methane is poorly soluble in water (e.g., 35 cm per kg of water at 17°C) but soluble in... 

A four-carbon compound is named butane, with the molecular formula of 411,0. Structures, molecular formulas, and some physical characteristics of these alkane-compressed gas compounds are shown in Figure 4.8. Notice the differences in boiling points and flammable ranges. As the carbon content increases, the boiling point of the compounds increases. In addition to carbon content, polarity and branching of compounds will affect physical characteristics. This concept will be discussed in more detail in Chapter 5. For now, just be aware that there are relationships between the physical characteristics of flammable gases, which include ignition temperature, heat output, vapor content, and vapor pressure. 

A common colorless and flammable gas at room temperature and pressure, propene is generally produced from coal or petroleum and is a nonrenewable resource. However, it can be used in combination with hydrogen peroxide (H Oj) and employed as an inexpensive rocket fuel propellant. Alkenes can also form branched compounds, just as the alkanes (Figure 4.11). However, in the case of the alkene, the main part of the name is always the portion containing the double bond. And, it is important to identify the carbon atom from which the branch comes. Some examples of the names... 

Methane, also referred to as marsh gas, is a gas composed of carbon and hydrogen with a chemical formula of CH4. It is the first member of the paraffin or alkane series of hydrocarbons. It is lighter than air, colorless, odorless, tasteless and is flammable. It occurs in natural gas and as a by-product of petroleum refining. In atmospheric burning no smoke production normally occurs. In air methane bums with a pale, faintly luminous flame. With excess air carbon dioxide and water vapor is formed during combustion, with an air deficiency carbon monoxide and water is formed. It forms an explosive mixture with air over a moderate range. Its primary uses are as a fuel and raw feedstock for petrochemical products. 

The boiling point (bp) of ethylene is -105°C, and under ambient conditions it is a colorless gas. It has a somewhat sweet odor, is highly flammable, and forms explosive mixtures with air. Because of its double bond (unsaturation), ethylene is much more active than the alkanes. It undergoes addition reactions, as shown in the following examples, to form a number of important products ... 

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