Esters are non-hydrocarbon organic compounds which contain carbon, hydrogen and oxygen. An ester is the product of ‘esterification’ reaction occurring between a carboxylic acid and an alcohol. A molecule of water is eliminated when a carboxylic acid combines with an alcohol to form an ester. The diagram shows how esterification happes and where the water comes from:
The general formula of the esters is CnH2n+1COOCmH2m+1 with the values of n =0, 1, 2, 3…, and m =0, 1, 2, 3… The values of n and m indicate the numbers of carbon atoms in the ester molecule. The functional group of the esters is known as carboxylate group (-COO). The structure has shown below:
Esters have many uses in both the living world and industries. Esters called parabens are used as food and drug preservatives because they can prevent the growth of microorganisms such as molds and yeast. Furthermore, esters have sweet fruit smells and with low molecular mass. Their properties make them suitable for the preparation of cosmetics and perfumes. The lower the molecular mass, the stronger the odors they carry are. These esters are used as food additives to improve the flavor and smell of processed foods. They are listed as ‘artificial flavours’ on labels of processed foods. The following table gives some ester flavours and fragrances:
In addition, the small esters like ethyl ethanoate are excellent solvents for organic compounds. Sunburn lotions, nail polish removers, plasticisers and glues use esters as solvents. For example, polystyrene cement is a mixture of polystyrene dissolved in ethyl ethanoate. When the ester evaporates, a solid plastic is left behind to bind together the surfaces being joined. Besides, large esters are used in the production of soaps and detergents. Soaps and detergents can remove dirt from surfaces of human skin, shirts and other solids when dissolving in water. Moreover, esters are also used in the production of polyester. The long-chain polyester molecules are unreactive and have great tensile strength. Hence, they are used to make polyester threads in the production of synthetic fabrics. Polyester is very durable and resistant to most chemicals, stretching and shrinking, wrinkle resistant and abrasion resistant. It is also hydrophobic in nature and quick drying. It can be used for insulation by manufacturing hollow fibers.
The point is that you can't be too greedy."
"You have to think anyway, so why not think big?"
"I'm a bit of a P. T. Barnum. I make stars out of everyone."
"If you're going to be thinking, you may as well think big."
"I wasn't satisfied just to earn a good living. I was looking to make a statement."
"Sometimes your best investments are the ones you don't make."
"Sometimes by losing a battle you find a new way to win the war."
"“Anyone who thinks my story is anywhere near over is sadly mistaken.”"
"“As long as you are going to be thinking anyway, think big.”"
"“Everything in life is luck.”"
The point is that you can't be too greedy."
"You have to think anyway, so why not think big?"
"I'm a bit of a P. T. Barnum. I make stars out of everyone."
"If you're going to be thinking, you may as well think big."
"I wasn't satisfied just to earn a good living. I was looking to make a statement."
"Sometimes your best investments are the ones you don't make."
"Sometimes by losing a battle you find a new way to win the war."
"“Anyone who thinks my story is anywhere near over is sadly mistaken.”"
"“As long as you are going to be thinking anyway, think big.”"
"“Everything in life is luck.”"
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Donald Trump
11/6/2019 04:59:27 am
Yeah this is me...all you silly little people with your big heads are mistaken for everything in life is luck clearly...I got here where I am that way...yeah I won that election. Now who says that school is any different; Anyone who thinks my story is anywhere near over is sadly mistaken as I am not done on this chapter here...you need to think on how this logically may affect my great America with your words of random and not funny enough style...for you see I have that style...bow to your new overlord...
Love, The US President Of The United States Of America Donald Trump...
P.S: Please vote for me in the next election, that wall still needs to be built, so don't forget or there will be consequences...
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