Tieng anh nganh hoa

EXERCISES
A. Read and translate into Vietnamese
acetone, ketone, pungent, aromatic odor, organic solvents, ether, methanol, ethyl alcohol, ester, synthesis,
unaffect, permanganate, flash point, coal peat, lime, cellulose acetate, photographic film, plastics,
dehydrogenation, promoters, exothermic, petroleum
B. Answer the following questions
1. What is acetone?
2. What is acetone chiefly used for?
3. Does acetone occur in human body? and where does it exist?
4. What is the largest usage of acetone?
5. Describe some methods of production of acetone.
C. Translate into English
1. Axêton là mt cht lng không màu, linh ng, có th cháy cho mùi hi cay và có th xem nh mùi
hi thm.
2. Axêton còn c hình thành do quá trình phân hy bi nhit cao ca than bùn, các mui ca axit
axêtic, axit xitric và bng quá trình chng ct khan ca ng vi nc vôi.
UNIT 25: ACETIC ACID
Certainly acetic acid is the most familiar of all the organic acids. It is best known as the chief acid
constituent of vinegar. When cooled to below 16 degrees, pure acetic acid forms colorless crystals. These
crystals resemble ice in appearance; hence the pure acid is usually called "glacial" acetic acid.
There are many ways to prepare acetic acid. It can be obtained by the oxidation of ethyl alcohol
which in turn is prepared by fermentation. Or, it can be obtained from cider vinegar which is prepared
from the juice of apples. For a long time acetic acid was produced by the distillation of wood. Seven
gallons of acid were extracted from one ton of wood. Acetic acid is also produced by synthetic methods. One
such method employs acetylene as the starting point which itself is obtained as a by-product in the production
of hydrogen during the refining of petroleum. The acetylene is passed through a dilute solution of sulfuric acid
containing a catalyst. Acetaldehyde is formed by this reaction and is then oxidized to acetic acid.
The most convenient way to prepare glacial acetic acid in the Lab is by the distillation of sodium
acetate with sulfuric acid. Place 10 grams of sodium acetate in an evaporating dish. Apply gentle heat and
continue heating, with stirring, until the water of crystallization is driven off and a dry powder remains.
Be very careful not to heat too strongly, as the compound will decompose and char. Transfer the powder
to a flask and add 7 cc. of concentrated sulfuric acid. If a condenser is available, fit it quickly to the flask.
If not, substitute a one-hole stopper and glass tubing leading to another vessel immersed in ice water.
Heat gently. Acetic acid distils over and collects in the receiving container. If you care to purify the acid,
it must be distilled again and that potion boiling at about 116 degrees should be collected.
To demonstrate how easily acetic acid freezes, immerse a partially filled test tube of the pure acid
forms salts. For example, neutralization with sodium carbonate will produce sodium acetate. And, using
calcium carbonate, calcium acetate is obtained. By heating dry calcium acetate, acetone is produced.
Similarly, ammonia will produce ammonium acetate and from this compound acetamide is prepared.
With organic alcohols, acetic acid forms esters.
EXERCISES
A. Read and translate into Vietnamese
familiar, constituent, vinegar, in appearance, glacial acetic acid, fermentation, cider, juice, of apples,
acetylene, refining, gentle, chat, acetaldehyde, decompose, vessel, immerse, collect, receiving, container,
neutralization
B. Answer the following questions
1. What is the acetic acid?
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