How To Write A Lab Report Using Qualitative Analysis Of Cations

To determine which ions are present in the two unknown solutions. This will be accomplished by mixing three known solutions with three testing solutions. You will use this information to determine which ions are present in the unknown solutions.

Reaction 2 - 1.Used a Beral- type pipet, added about 2mL (40 Drops) of 1M hydrochloric acid solution to a small test tube.

We then proceeded in testing for excess Ca2+ by adding two drops of .5 M K2C2O4 to test tube two and attentively observed to see if a precipitate formed, which it did. This meant that Ca2+ was in excess and C2O42- was the limiting reactant in the original salt mixture. We then cleaned up. Upon returning to our next class, we took the filter paper, with the precipitate on it, and took its mass.

In experiment A the results from the precipitation of CaC2O4 H2O from the salt mixture were obtained by weighing the items listed on Table 1 on a scale.

The two most obvious formation of the precipitate were the combinations with the MgSO4. The MgSO4 and NH3 solution became very opaque and the MgSO4 and Na2CO3 turned from liquid to a full solid white substance. The Na2CO3 and CH3COOH did not have as strong of a reaction, however, the precipitates were able to be visualized with in the clear

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

5. Was there any evidence that some of the copper (II) chloride was left in the beaker? Explain.

The objective of this experiment will be to combine various substances, liquids and metals, and to observe their behavior when they are combined. The types of reactions observed shall determine the nature of these reactions: physical or chemical.

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

7. NiSO4, nickel sulfate was in the past very valuable and it is recognized by its “envious” green nature.

The wet, crude product was placed into the 50 mL Erlenmeyer flask. Small amounts of CaCl2 were added to dry the solution. The flask was sealed and the mixture was swirled and left to settle. Once

The volume of a small test tube and a thin-stemmed pipet were determined in this section of the lab. Water was poured into a small test tube until the water reached the very top edge of the test tube. The test tube was then emptied into a plastic 25 mL graduated cylinder and volume was measured and recorded into data table 3. A think-stemmed pipet was completely filled with water. Drops were carefully counted and emptied into the empty plastic 25 mL graduated cylinder until the water level reached 1 mL. The number of drops in 1 mL was recorded into data table 3. The thin-stemmed pipet had a total volume of 4 mL and that was also recorded into data table 3.

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

Miller and Urey used an enclosed apparatus that was vacuumed sealed so conduct their experiment. The apparatus was filled with

The metal ions tested were calcium, copper, iron, lead, and barium. The anions tested were sulfate, carbonate, phosphate, and chloride. Table 1.1 represents the observations from the chemical reactions with the metal ions and Table 1.2 represents the observations from the chemical reactions with the anions. A scheme was built based on the two tables when a precipitate formed. The unknown metal ion was named Bloody Baron and when NaCl was added, no precipitate was formed, therefore, it couldn’t be lead. When H2SO4 was added, it could not contain barium because no precipitate was formed. Suddenly, when NH3 was added, the color turned indigo just as copper did and a little bit of a precipitate formed so iron was noted according to Table 1.1. Finally, as Na2C2O4 was added, no precipitate formed and, according to Table 1.1, iron was the only thing that did not form a precipitate. The conclusion of the unknown metal ion was correctly proven to contain iron and copper. The unknown anion was named Edward Scissorhands and it was only tested with silver nitrate (AgNO3) and barium chloride