.

.

Biyernes, Oktubre 31, 2014

HYDROCARBONS

Before we proceed thoroughly, why don’t we talk first what hydrocarbons are?



The simplest organic compounds are HYDROCARBONS, which contain only the elements Carbon and Hydrogen. How many different compounds do you think two elements can form? You might guess that only a few compounds are possible. However, thousands of hydrocarbons are known, each containing only the elements Carbon and Hydrogen. 
Hydrocarbons are the principal constituents of petroleum  and natural  gas. They serve as fuels and lubricants as well as raw materials for the production of plasticsfibresrubbers, solvents, explosives, and industrial chemicals.
Many hydrocarbons occur in nature. In addition to making up fossil fuels, they are present in trees and plants, as, for example, in the form of pigments called carotenes that occur in carrots and green leaves. More than 98 percent of natural crude rubber is a hydrocarbon polymer, a chainlike molecule consisting of many units linked together. The structures and chemistry of individual hydrocarbons depend in large part on the types of chemical bonds that link together the atoms of their constituent molecules.


The following are Different Hydrocarbon Compounds and Hydrocarbon Derivatives with their Uses:





Hydrocarbons in Fuel
          Hydrocarbons containing between six and 10 carbon molecules are the top components of most fuels, regardless of whether they are alkanes, alkenes, or cyclic. In general, these molecules are burned to produce energy. Burning hydrocarbons requires oxygen. The hydrocarbon  and oxygen combine, in a process called combustion, to produce water, carbon dioxide, and energy. Of course, these molecules are not the only products of the combustion of hydrocarbon. Hydrocarbons that are contaminated with atoms such as sulfur and nitrogen will also produce nitrogen dioxide and sulfur dioxide.
          Today, many hydrocarbons are obtained from a fossil fuel called PETROLEUM. Petroleum formed from the remains of microorganisms that live in Earth's oceans millions of years ago. Over time, the remains formed thick layers of mud-like deposits on the ocean floor. Heat from earth's interior and the tremendous pressure of overlying sediments transformed this mud into oil-rich shale and natural gas. In certain kinds of geological formations' the petroleum ran out of the shale and collected in pools deep in Earth’s crust. Natural gas, which is formed at the same time and in the same way as petroleum, is usually found, with petroleum deposits. Natural gas is composed primarily of methane-the simplest hydrocarbon but it also contains small amount of other hydrocarbons that have from 2 to 5 carbon atoms.


Because the structure of different hydrocarbons can vary so drastically, the properties of each class of molecule vary greatly as well. In order to help categorize the properties of hydrocarbons, they are broken up into several basic types.



         ALKANES are organic compounds that consist entirely of single-bonded carbon and hydrogen atoms and lack any other functional groups.


         METHANE is the smallest member of a series of hydrocarbons known as alkanes. It is used as a fuel in homes and science laboratories and is a product of many biological processes. Methane is used in industrial chemical processes and may be transported as a refrigerated liquid (liquefied natural gas, or LNG). While leaks from a refrigerated liquid container are initially heavier than air due to the increased density of the cold gas, the gas at ambient temperature is lighter than air. Gas pipelines distribute large amounts of natural gas, of which methane is the principal component.We are all familiar with the use of propane in gas barbecues, lanterns, and as a fuel for internal combustion engines and heating systems PROPANE also known as LP (liquefied propane) gas is sold as a fuel for cooking and heating. BUTANE is also a readily available fuel, familiar to everyone in the form of the pocket lighter and used as a fuel in some torches. It is also used in the manufacture of synthetic rubber. 


With pentane, the saturated hydrocarbons enter the realm of room-temperature liquids. This makes them useful as organic solvents, cleaners, and transport fuels. Gasoline for internal combustion engines in cars, trucks, tractors, lawnmowers, and so on, is rated in combustion properties relative to octane. It is in fact a combination of liquid hydrocarbons ranging from hexanes to decanes.


ALKENESare unsaturated compounds that contain at least one carbon-to-carbon double bond. Another term that is often used to describe alkenes is olefins

            Plants produce ETHENE (ETHYLENE)-an alkene, as a natural ripening hormone. For efficiency in harvesting and transporting products to market, fruits and vegetables are often pick while unripe and are exposed to ethene so they will ripen at the same time. 




           It also plays a part in causing leaves to fall from deciduous trees in preparation for winter. Ethene is also a starting material for the synthesis of the plastic polyethylene, which is used to manufacture many products, including plastic bags, rope, and milk jugs. Other alkenes are responsible for the scents of lemons, limes, and pine trees.  

ALKYNES are organic molecules made of the functional group carbon-carbon triple bonds. They are written in the empirical formula of CnH2n-2. They are unsaturated hydrocarbons.

ETHYNE-an alkyne, also known as acetylene is a by-product of oil-refining and is also made in large quantities by the reaction of calcium carbide (CaC2) with water. When supplied with enough oxygen, ethyne burns with an intensely hot flame that can reach temperature as high as 3000˚C. Acetylene torches are commonly used in welding.

The adjective "AROMATIC" is used by organic chemists in a rather different way than it is normally applied. It has its origin in the observation that certain natural substances, such as cinnamon bark, wintergreen leaves, vanilla beans and anise seeds, contained fragrant compounds having common but unexpected properties. Cinnamon bark, for example, yielded a pleasant smelling compound, formula C9H8O, named cinnamaldehyde


BENZENE, TOLUENE, and XYLENE are aromatic hydrocarbons. They are once used as industrial and laboratory solvents. However tests have shown that the use of such compounds should be limited because they can affect the health of people who are exposed to them REGULARLY. Health risks linked to aromatic compounds includes respiratory ailments, liver problems, and damage to the nervous system. Beyond these hazards, some aromatic compounds are carcinogens, which are substances that can cause cancer. 

Yes, there are many uses of Hydrocarbons that makes them very important in our today's civilization. Without them, it would not be easy for us to work especially with the use of machines, because many hydrocarbon derivatives such as petroleum were commonly used as fuel. We just only have to make it safe in dealing with them. We have to be careful and use them properly for us and also for the other people to be safe. For example, gasoline which is a mixture of different hydrocarbons was mainly used as fuel to car engines. It has different characteristics such as flammability. In order to reduce the risks of causing fire, we have to store them properly and put them away from fires that can cause them to blaze up. 


Not all hydrocarbons are too much dangerous. The only thing we have to do is to make every step safe and follow the instructions in applying the products. And although there are some hydrocarbon that is harmful to one's health, experts and professionals are playing their important roles to protect us and other people. 


Thank you for reading this blog… I hope you’ve learn so much about hydrocarbons, all about their uses and also about everything that they could harm people and how we could prevent them… Not only I alone, but also with the help of my members so we were be able to produce this topic.  So this is the end of this blog thanks for everything!