How to Properly Clean Laboratory Glassware

Cleaning laboratory glassware isnt as simple as washing the dishes. Heres how to wash your glassware so you wont ruin your chemical solution or laboratory experiment. Lab Glassware Cleaning Basics Its generally easier to clean glassware if you do it right away. When a detergent is used, its usually one designed for lab glassware, such as Liquinox  or Alconox. These detergents are preferable to any dishwashing detergent that might be used on dishes at home. Usually, detergent and tap water are neither required nor desirable. You can rinse the glassware with the proper solvent, then finish up with a couple of rinses with distilled water, followed by final rinses with deionized water. Washing Out Common Chemicals Water Soluble Solutions  (e.g., sodium chloride or sucrose solutions): Rinse three to four times with deionized water, then put the glassware away.Water Insoluble Solutions  (e.g., solutions in hexane or chloroform): Rinse two to three times with ethanol or acetone, rinse three to four times with deionized water, then put the glassware away. In some situations, other solvents need to be used for the initial rinse.Strong Acids  (e.g., concentrated HCl or H2SO4): Under the fume hood, carefully rinse the glassware with copious volumes of tap water. Rinse three to four times with deionized water, then put the glassware away.Strong Bases  (e.g., 6M NaOH or concentrated NH4OH): Under the fume hood, carefully rinse the glassware with copious volumes of tap water. Rinse three to four times with deionized water, then put the glassware away.Weak Acids  (e.g., acetic acid solutions or dilutions of strong acids such as 0.1M or 1M HCl or H2SO4): Rinse three to four times with deionized water before putting the glassware away.Weak Bases  (e.g., 0.1M and 1M NaOH and NH4OH): Rinse thoroughly with tap water to remove the base, then rinse three to four times with deionized water before putting the glassware away. Washing Special Glassware Glassware Used for Organic Chemistry Rinse the glassware with the appropriate solvent. Use deionized water for water-soluble contents. Use ethanol for ethanol-soluble contents, followed by rinses in deionized water. Rinse with other solvents as needed, followed by ethanol, and, finally, deionized water. If the glassware requires scrubbing, scrub with a brush using hot soapy water, rinse thoroughly with tap water, followed by rinses with deionized water. Burets Wash with hot soapy water, rinse thoroughly with tap water, then rinse three to four times with deionized water. Be sure the final rinses flows off of the glass. Burets need to be thoroughly clean to be used for quantitative labwork. Pipets and Volumetric Flasks In some cases, you may need to soak the glassware overnight in soapy water. Clean pipets and volumetric flasks using warm soapy water. The glassware may require scrubbing with a brush. Rinse with tap water followed by three to four rinses with deionized water. Drying or Not Drying It is inadvisable to dry glassware with a paper towel or forced air since this can introduce fibers or impurities that can contaminate the solution. Normally, you can allow glassware to air dry on the shelf. Otherwise, if you are adding water to the glassware, it is fine to leave it wet (unless it will affect the concentration of the final solution.) If the solvent will be ether, you can rinse the glassware with ethanol or acetone to remove the water, then rinse with the final solution to remove the alcohol or acetone. Rinsing with Reagent ​If water will affect the concentration of the final solution, triple rinse the glassware with the solution. Drying Glassware If glassware is to be used immediately after washing and must be dry, rinse it two to three times with acetone. This will remove any water and will evaporate quickly. While its not a great idea to blow air into glassware to dry it, sometimes you can apply a vacuum to evaporate the solvent. Additional Tips Remove stoppers and stopcocks when they are not in use. Otherwise, they may freeze in place.You can de-grease ground glass joints by wiping them with a lint-free towel soaked with ether or acetone. Wear gloves and avoid breathing the fumes.The deionized water rinse should form a smooth sheet when poured through clean glassware. If this sheeting action is not seen, more aggressive cleaning methods may be needed.

Triangular trade. - 970 Words

Analyze the role of slavery and Triangular trade in the Colonial mercantile structure and for the primitive accumulation of Capital that allowed the take off of Capitalism? The slave trade originated in a shortage of labor in the New World. The first slaves used were Native American people, but they were not numerous enough and were being decimated by European cruelty and diseases. It was also impossible to convince enough Europeans to migrate to the colonies, despite attempts to distribute free land. Massive amounts of labor were needed for mining, but especially for the plantations, in the labor-intensive growing, harvesting and processing of sugar, cotton and other tropical crops which could not be grown profitably in Europe. Growing†¦show more content†¦The slave ship sailed from the home country with a cargo of manufactured goods. These were exchanged at a profit on the coast of Africa for Negroes, who were traded on the plantations, at another profit, in exchange for a cargo of colonial produce to be taken back to the home country. As the volume of trade increased, the triangular trade was supplemented, but never supplanted, by a direct t rade between home country and the West Indies, exchanging home manufactures directly for colonial produce. The triangular trade thereby gave a triple stimulus to British industry. The Africans were purchased with British manufactures; transported to the plantations, they produced sugar, cotton, indigo, molasses and other tropical products, the processing of which created new industries in England; while the maintenance of the Negroes and their owners on the plantations provided another market for British industry. Thus, we see the close connection between the slave trade and the development of capitalism in Europe. Capitalism represents an increased use of machinery and increased demanded for more raw materials. This led to the colonization of the Americas to secure land (raw materials), and to the slave trade which supplied the needed labor. Merchants accumulated the profits from the sale of slaves andShow MoreRelatedTriangular Trade Route And The Middle Passage Essay1042 Words   |  5 PagesTriangular Trade Research Paper The triangular Trade Route was a system of transferring goods, imports, and people throughout three different ports. Items were transported between the West Indies, Africa, and New England. The most known case of the Triangular Trade Route was in the 17th and 18th century when North American colonies would trade specific goods, like rum, in return for African slaves. The transfer of the slaves was referred to as the middle passage. The middle passage was a harsh andRead MoreThe Transatlantic Slave Trade Often Known As The Triangular1411 Words   |  6 Pages The Transatlantic Slave Trade often known as the triangular trade was described as the largest long-distance movement of people in all of history. The movement of Africa slaves to the Americas lastly for approximately four centuries and can be viewed as one of the first ideas of globalization . The ship would move from the Americas to Western Europe with raw materials, then to Africa with manufactured goods. Lastly, from Africa the Americas with African slaves. Thus the movement of overRead MoreEssay on Triangular Trade1888 Words   |  8 Pagesten million Natives. This exploitation and the introduction of these diseases to these people was done through the â€Å"triangular trade†. The triangular trade is a historical term referring to the 18th-century trade between South America, New England, and the west coast of Africa. The commodities involved were several, but principally they were sugar, rum, and slaves. The trade brought much wealth to North America and the profits ultimately became the foundation of American capitalism. Sugar becameRead MoreThe Middle Passage Was A Major Aspect Of The Triangular Trade Essay1844 Words   |  8 PagesThe middle passage was a major aspect of the triangular trade, which involves the illegitimate trading of African captives in exchange for manufactured goods from the Europeans who later transport the African captives to the Atlantic world and then exchange them for raw materials from the Atlantic traders. The trading of the African captives to the Europeans in exchange for manufactured goods was executed by the African middle men. The African middle men were also responsible for the kidnapping ofRead MoreResistance and Oppo sition From the first slaves came resistance and rebellion in hopes of gaining700 Words   |  3 Pagesthe first slaves came resistance and rebellion in hopes of gaining freedom or simply to make the life of their owners miserable. The African people first began to rebel in their homeland. A number of attempts were made in Africa to either stop the trade or cut it down significantly.’ More attempts were made with the passing or laws preventing slave traders from trading in their village keeping that village safe. Many villages would fight against traders to keep trading from happening but they soonRead MoreMiddle Passage By Charles Johnson909 Words   |  4 Pages The book Middle Passage by Charles Johnson tells a story about the triangular slave trade which took place early in America s history. This book was written with such close attention to detail that it gave the reader a sense of what life was like on board a slave boat. Johnson s writing style included many different techniques including the use of varying structure, imagery and language. All of these devices helped create a very successful story about slavery. This book tells the story aboutRead MoreThe Terrible Trade Of The Slave Trade2324 Words   |  10 PagesTerrible Trade Screams for relief, cries for comfort, and moans for death all revolved around the slave trade. The slave trade is an event that not only impacted Africa, but the whole world even still today. This essay will explain how cultures were ruined and families were torn apart. The slave trade has influenced history worldwide because it has impacted continents economically, socially, and politically. The Middle Passage received its name because it is in the middle of the Triangular Trade. TheRead MoreThe Terrible Trade Of The Slave Trade2289 Words   |  10 PagesThe Terrible Trade Screams for relief, cries for comfort, and moans for death all revolved around the slave trade. The slave trade is an event that not only impacted Africa, but the whole world. This essay will explain how cultures were ruined and families were torn apart. The slave trade has influenced history worldwide because it has impacted countries economically, socially, and politically. The Middle Passage received its name because it is in the middle of the Triangular Trade. Legs of the triangularRead MoreThe Age Of Exploration And Its Effects On Economic And Political Power1611 Words   |  7 Pagesconvention would most certainly be the newfound relation between, capitalism and globalization and their effects on economic and political power. However some countries succeeded in their endeavour of international trade, while others did not. Europeans constructed and maintained their trade and territorial empires, whether through conquest, centralizing authority, religious conversion, commercial monopolies, or through conflict with other Europeans. Economics seems to be the most significant factorRead MoreMercantilism Essay1456 Words   |  6 Pagesinstills that a country’s wealth is based upon the amount of gold and silver it has amassed. It also instills that wealth is correspondent to the country’s trade value. In many Mercantilist countries the gove rnment is pushed to encourage a greater number of exports than imports, or a positive balance of trade. In order to keep this favorable balance of trade, several countries used taxes, tariffs, and subsidies making imports more and more unaffordable. Philipp Wilhelm von Hornick an Austrian Economist

Impact Diet on Health Free Essays

Diet makes people think as a weight loss regime. The majority of people think it is products with low calories, and help you to control your weight. But the actual meaning is a process of eating food or nutrients vitamins. We will write a custom essay sample on Impact Diet on Health or any similar topic only for you Order Now Healthy diet and nutrition have a positive impact on human health. On the other hand poor diets have harmful lasting effects. If a human does not have a good diet the body won’t have any nutrients to play the inside role of the body. Nutrition helps your body to be strong and to fight against diseases. Unhealthy diet can have consequences with physical body, as well as can affect your thinking and mental job. A poor diet can result to many health issues, such as heart disease, high blood pressure high levels of cholesterol, asthma, sometimes even diabetes. But a very dangerous problem usually caused by eating less than you are supposed to can cause Anorexia.. This mental and physical disorder is usually found in athletes, models or ballet dancers, who aim to get thin day by day. This syndrome can be found in normal people who have an unhealthy poor diet. It is more towards a physiological disorder, there is a stage of Anorexia Nervosa is when person is constantly dieting carrying to an extreme level, and that is Dale. Dale is when people try to loose much more weight than necessary, and they still feel overweight. They see themselves as very fat, and that’s what makes them to keep on loosing weight. Force feeding anorexic people does not work, since there brain is mentally trained not to eat, therefore they will throw up if they are force fed. Having a poor diet can result many physical effects related to the extreme weight loss. Heart rate can increase, BMR, in addition to the body temperature all drop to low levels. When the fat in the human body is used, the body breaks the muscle tissue for energy, and that can result to heart damage. As well as if this disorder occurs in an age of puberty the body growth stops. Anorexic victims usually have low confidence level which in generally cause of this disorder. The science has not found the exact treatment for this; but however a small treatment requires a team of professionals, physicians, nurses, psychiatrist and dieticians- to work together. Mental condition analysis is required to treat this. This treatment plan is developed that deals with physical effects of anorexia and mental reasons for its occurrence. It sometimes involves force feeding, and however does not work with most of the patients. The benefits of the treatment are that psychiatrists and dieticians try to convince the person to eat, as well as knowing the reason for occurrence. A drawback is that there is no certain cure for this, as well as it is very hard to encourage anorexic people to eat, it is very hard to put them back on the right track. At the same time as well as there is no medicine that can help to cure anorexic people. The social impact of anorexia is the relationship among family and friends can be in tense as the anorexic becomes more and more obsessed with not eating, and tried to stay away from gatherings and parties in fear of force feeding. As well as this disease can be caused by political reasons. E. g. in some countries the distribution of cops is equal and if a family is not able to feed the children that will result to a poor diet and since the children are expected to work on the farms that means too much exercise and poor diet. And when the children get used to it, they do not feel hungry anymore and that is when anorexia can occur. Furthermore in some cultures or old traditions parents do not feed their daughters, or otherwise they will get fat and nobody will marry them. So they try to feed as least as possible and in addition to they can afford that much. If day by day they get less food than they are used to it, and get thin so much that don’t even realize. Also in some European countries they are forbidden to show slim models on TV and in mass media advertisement, since the fans admire it so much they follow the celebrity. By not showing them this it can help to prevent it. . Every human being should look after their diet; they should apply all the vitamins nutrients their body requires. All individuals should have a diet, and shall be aware of the amount of nutrients they receive. Poor diet also consists of less nutrients, but also unhealthy food that does not help your body to cooperate with you. Anorexia is nowadays very common among people. Not knowing the reason behind it. And after a person has anorexia it is almost impossible to put him/her on the right track. Anorexia can lead to different stage, at a level where there is high risk of death. There are no single causes that may influence upon occurrence of anorexia. Usually, all 2 factors are brought into play: The psychological factor- influence of the family and internal conflicts The social factor- influence of environment, expectation, imitation (watching celebs on the TV, your friends around you, you are being insulted that you are fat) However there is no easy cure for this, so care for yourself, accept yourself, and you will never be caught into the trap of inferiority complex. How to cite Impact Diet on Health, Papers

Japanese Culture free essay sample

Compares insights into Japanese culture, value systems, roles of Japanese Amer. women, ethnocentrism, ethics, modernization. The Chrysanthemum The Sword ( Ruth Benedict ) The Japanese Mind (Robert C Christopher ) A key element of Japanese culture is the cuisine. Japanese food itself is driven by the geography of the country, and the rituals surrounding eating and drinking are derived largely from Shinto belief. Noodles, fish and rice are the staples of Japanese cuisine. That Japan is an island nation results in seafood being the primary source of protein, and some of the worlds most famous fish markets are in Japan. Fish is often consumed raw, either on its own (sashimi) or in rolls (sushi). Japanese cuisine often features noodle soups, flavored with seasonings such as miso or dashi that are derived from local ingredients. In all but the most cosmopolitan cities such as Tokyo, Japanese cuisine is the only form of food to be found easily. We will write a custom essay sample on Japanese Culture or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page