The objective of the experiment was to identify the unknown salt that was given. The unknown salt contained an anion and a cation labelled, 38A. A series of preliminary tests were first conducted in order to help choose which confirmation tests should be used to identify the compound. The preliminary tests included pH and solubility, and the behaviour of the salts with concentrated sulfuric acid. The compound was found to have a slightly acidic pH, around 6.9 while being soluble in water. The compound showed no change in properties after the addition of concentrated sulfuric acid. The confirmation tests were then divided into two parts, one for the identification of the cation and the other for the identification of the anion.
The anion tests
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A solution of the salt was prepared and 4 drops of AgNO3 (10%) solution were added. This created an off-white creamy precipitate. In order to be sure that this was not a false positive, three drops of nitric acid (6 M) were added. As the precipitate did not dissolve this meant that the unknown anion had a halide. To confirm which halide it was, a fresh solution of the salt was created and acidified with a few drops of HNO3 (6M). This was accompanied by 1ml of chloroform, an organic solvent. The addition of a few drops of NaOCl solution, swirled gently as the drops made contact with the unknown created a brown-yellow …show more content…
The observation of chemical behaviours under specific conditions allowed for the use of process of elimination. Given the observations found in the materials and methods section and the data found in the lab manual1 it was found that the anion was not acetate or carbonate, but rather a halide, specifically Br due to the brown-yellow hue of the organic layer. The observations for the cation test along with the data from the lab manual1 showed that the unknown was from group II. Since the flame test showed no observable difference this allowed for the conclusion that the cation was Mg2+.
For the anion, the most difficult test was the acetate test as the test was concentration dependent and it also relied on colour as its identifier. This was difficult to achieve as the concentration was hard to keep constant, and the colour was difficult to pinpoint. Possible solutions include getting access to a Drypette TM, a manual powder pipette that would dispel a more accurate sample of salt. This would then make for a more reliable consideration of the color as an indicator of the presence of
The hypothesis is correct. Potassium chloride mixed with silver nitrate creates a white precipitate. Barium
When dealing with glass objects such as a glass beaker or thermometer, be sure to hold the item. In instances where glass is broken during the experiment, do not clean up the area yourself! Notify your instructor immediately.
In reference to the analysis of anions, Table 1 shows that a precipitate was formed when our unknown was combined with HNO3 and AgNO3, thus indicating the presence of a chloride ion. Because our unknown did not form a precipitate due to HCl and BaCl2, separate, effervesce, or smell, we concluded that neither sulfate, nitrate, carbonate nor
World War Two resulted in a chaotic destruction that overwhelmed Europe. These feelings of dismay are concisely summarized in Ruta Sepetys’ Salt of the Sea.. An impactful quote states, “war had bled color from everything, leaving nothing but a storm of gray.” The war in 1945 had drained any and all feelings of hope and spirit out of European people. In it’s wake, the war left a cloud of devastation and despair. Florian and Joana have to overcome this war, their fate, and guilt in order to return to their past selves and survive their journey in a German and Russian warzone.
The 1954 film Salt of the Earth directed by Herbert J. Biberman, is set in New Mexico and is about the Hispanic miners working for Delaware Zinc, a mining company, and the plot of the movie is about how the miners go on strike till they are treated equally the same as the other non-Hispanic miners. The miners’ strike goes on for months and the company decides to hold out on the workers by scaring the old workers with new miners to take their jobs, and during that time the wives of the miners decided to take it upon themselves to put themselves on the frontlines with the men because the women are also fighting for something else sanitation. News gets out about the strike and many supporters send letters with money
The purpose of this semester long experiment was to determine an unknown organic acid. An organic acid is an organic compound with acidic properties. A base reacts with acids to form salts. Titrations are used to determine the concentration of unknown substances. The purpose of the KHP experiment was to determine the molarity of NaOH. HCl titrations are mainly to check technique and used to verify the molarity of NaOH solution. The hypothesis is that this acid is C4H3OCOOH.
In this experiment, an unknown Grignard reagent was prepared from an aryl halide. The unknown reagent was then reacted with carbon dioxide to form a carboxylic acid. The solid acid was then isolated and recrystallized before the melting point was taken. The precipitate was then dissolved in water and titrated to determine the molecular weight. The melting point and molecular weight were then used to determine the unknown acid obtained from the experiment.
Based the data collected, the identity of the unknown #42 is lithium chloride. Because the unknown compound produced a bright red pinkish flame, shown in Table 1, the possible cations based on the CRC Handbook were lithium or strontium 1.The known 1M lithium chloride also produced the same colored flame as the unknown, suggesting that the unknown compound has lithium. Since lithium produces no precipitate with the compounds in Table 2 and strontium produces a precipitate with the same compounds, the observations in Table 2 indicate that the unknown’s cation is lithium 4. Using the solubility table, process of elimination, and the results in Table 3 the possible anions for the unknown compound were chloride and bromide4. The production of precipitate
Purpose of this experiment was to find the amount and percent of water in a hydrated salt. Also, to successfully determine percent error and standard deviation. Hydrated salts are substances that occur naturally who usually contain an amount of water molecules chemically bonded to the compound. A few hydrated salts have weak bonds within the water molecules which allows heat to remove the water molecules creating an anhydrous salt. Hydrated salts that lose water molecules to the atmosphere without a heat source are known as efflorescent. Salts that readily absorb water are called deliquescent. An example of an anhydrous salt would be Magnesium Sulfate or also known as Epsom Salt. Epsom salt separates under heating and becomes
the ions of SO42-, CO32-, Cl-, and I-,identify them separately, and use the observation to identify the unknown.
The next day an orange goopy textured product resulted. The extracts were then dried and combined with anhydrous sodium sulfate, then evaporated with dry air under the hood in a warm water bath. The liquid was cooled and had an initial weighing of 0.5887g. It was reweighed several minutes later with a final
Identifying this organic acid was an extensive task that involved several different experiments. Firstly, the melting point had to be determined. Since melting point can be determined to an almost exact degree, finding a close melting point of the specific unknown can accurately point to the identification of the acid. In this case the best melting point
“Salt, A World History,” is an extensive aspect of world history by Earth’s one edible rock - salt. The book begins at the start of recorded history, and highlights humanity’s dependence on salt, up to roughly present day times. It focuses on the effect salt had on, and its contributions to, humankind. The book details how salt affected, economics, religion, science, and culinary practices all over the world.
The main objective of this experiment is to carry out qualitative analysis to identify metal cations in unknown solution 1.
The cations in both the known and unknown samples were identified by using qualitative analysis, of which were determined to be acidic, basic, or neutral by using litmus paper. Acid-base reactions, oxidation-reduction reactions, and the formation of complex ions are often used in a systematic way for either separating ions or for determining the presence of specific ions. When white precipitate formed after adding hydroxide, aluminum ion was determined to be present in the solution. However, nickel was determined to test positive when the solution changed to a hot pink color after adding a few drops of dimethylglyoxime reagent and iron was present when the solution was a reddish brown color when sodium hydroxide was added to the mixture at the very beginning of the experiment. Qualitative analysis determines that ions will undergo specific chemical reactions with certain reagents to yield observable products to detect the presence of specific ions in an aqueous solution where precipitation reactions play a major role. The qualitative analysis of ions in a mixture must add reagents that exploit the more general properties of ions to separate major groups of ions, separate major groups into subgroups with reactions that will distinguish less general properties, and add reagents that will specifically confirm the presence of individual