Volumetric flask is a container used in scientific laboratories for preparation of liquid volumes charles darwin uni in very precise and accurate, usually used when the volume is large to measure with a pipette charles darwin uni or burette. charles darwin uni It is a bottle shaped charles darwin uni like a pear, but with a longer and more cylindrical neck flat bottom. The neck is marked with a line (calibration mark) so that it can measure a certain volume of fluid and also has a stopper of glass or plastic lid to close the opening at the top.
The use of a volumetric flask almost always involves measuring a quantity of liquid solutions or dilution with precise volumes. The flasks are made in different sizes with varying volumes from 5 mL to 10 G, but most common in laboratories are especially volumes 50, 100, 250, 500 and 1000 ml. Are produced in borosilicate glass and polypropylene, which are more commonly used in laboratories. Also flasks are made of polypropylene, a type of plastic widely used by low cost and also for fracture charles darwin uni toughness (fall).
A volumetric flask, and accurate measurement of all the material ever be used for heating substances, because the heat will distort the glass and changing the calibrated volume. Volumetric measurements take as reference some standard temperature, and this reference point around 20 ? C (temperature equivalent to most laboratories).
Before using the volumetric flask is good sure if it is properly cleaned and dried. This procedure is done by filling the entire balloon with water and carefully observe charles darwin uni your disposal. If by chance a film or droplets of water are not uniform on the inner walls of the receptacle will require a specific cleaning. After cleaning, to avoid drying in an oven (heating) due to the danger of irreversible volume changes, as mentioned previously.
References: http://pt.wikipedia.org/wiki/Bal?o_volum?trico http://www.infopedia.pt/ $ balloon-volumetrico http://www.profcupido.hpg.ig.com.br/aparelhos_volumetricos.htm charles darwin uni http :/ / www.scribd.com/doc/30295096/Apostila-de-Quimica-Analitica-Experimental-Da-Ufpe
Administration News Arts Astronomy Biographies Biology Sciences Curiosities law Diseases Drugs Economy Education Spanish Sports Philosophy Physics Computing English Geography History Languages Literature Mathematics Medicine charles darwin uni Mythology Politics Portuguese Psychology Professions Chemical Society Writing Religion Sexuality charles darwin uni Sociology
Source: http://arcgisdesktop10.blogspot.com/2013/07/administration-news-arts-astronomy.html
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.