h) A way to make hard water softer is to put an sodium nitrate and create a precipitate to mellow out the reaction. Another way of making it softer is by removing the calcium ions one way of doing that is by boiling the solution to take out some of the ions. Conclusion: Overall, we determined that sodium carbonate, Na2CO3, is the anion that can be used to precipitate the most metal cations. Also, we learned that the anion sodium chloride, NaCl, could be used to remove silver ions from solutions. The stuff that I found interesting was that how many colours you can get when you mix the cations and anions
Lesson written by Carolina Sylvestri Experiment: Reaction Between Ions in Aqueous Solutions The Monster Mash Background: Ionic solids dissolve in water to form aqueous solutions which conduct electricity. These solutions contain both positive and negative ions in such numbers that their net electric charge is zero. In this experiment, you will mix various ionic solutions, two at a time, to determine which combinations form precipitates. Knowing which ions are present makes it possible to deduce which of the possible ion combinations are responsible for the precipitates. From your data table, it will then be possible to generate a solubility table.
EXPERIMENT 10: Solubility of Ionic Compounds Aim: How can we determine the solubility rules of ionic compounds? Materials: dropper bottles containing aqueous solutions of CaCl2, NaI , Na3PO4, AgNO3, CuSO4, NH4OH, , NaOH, and Na2CO3, plastic spot plates Introduction: A precipitation reaction occurs when two ionic compounds react in an aqueous solution to produce a precipitate, an insoluble (not soluble) substance which falls out of the solution. These reactions are a type of double-replacement, because the cations and anions of the reactants “change partners” in the products. For example: AgNO3 (aq) + NaOH (aq) ( AgOH (s) + NaNO3 (aq) According to Reference Table F, salts with hydroxide ions (OH-) are usually insoluble, and the silver ion (Ag+) is not an exception to this rule, so the AgOH that is formed will precipitate. However, in many instances, no precipitate forms because the recombination of ions yields only soluble compounds.
| Centrifuge: used to isolate the solid from the solution | . Focus Questions: When acidified water is not used in the zinc and iodine synthesis, zinc hydroxide is formed. How can it be identified based on the amphoteric nature. When zinc and iodine react without the presence of acetic acid in the water, zinc hydroxide forms. This is evident because the substance tested positive for both the acid test and the base test for zinc hydroxide.
An aqueous solution of potassium chloride is mixed with an aqueous solution of sodium nitrate. Identify the solid in the balanced equation. A) KCl B) NaNO3 C) KNO3 D) NaCl E) There is no solid formed when the two solutions are
The reaction that occurred with this step was displacement and metathesis in the form of gas formation. The balanced equation of this step looks as follows: CuSO4aq+Zns→Cus+ZnSO4(aq) Once this step was finished, the remaining copper was retrieved. First, to recover the copper HCl was added to remove all the zinc. When this happened, a yellow tint was observed in the liquid, as well as bubbling as the zinc was broken down. Once the copper dried out, it was weighed and came to a total of 240 mg.
Carbonate could be used to remove silver ions. This is because when carbonate reacts with a cation other the H+ and NH4+, it has a low solubility. Meaning it would form a precipitate with silver and the ions would be removed. Evidence that suggest nitrate compound are soluble is that they didn’t with most compounds, they remained aqueous. Also, there was never a formation of a precipitate when reacting with nitrate ions.
For the identification test for the gray solid, we all concluded that this substance showed negative results for every chemical tested except for the zinc metal. In other words, this gray solid only significantly reacted with HCl, indicating the presence of zinc metal. However, our test for the iodide ion with the gray solid, where we added AgNO3 to the gray solid, was very unclear as we did see a yellow liquid, which we could not decide whether it was a precipitate of AgI. Other substances produced a clear precipitate but this one did not. So we concluded that this Zinc did not contain significant amounts of iodide ion.
Focus Questions: 1) What happens Qualitatively on both the Macroscopic and Atomic levels when zinc, Iodine and Acidified Water are mixed? Does a Reaction Occur? On the Macroscopic Levels, there is no reaction. However, when Zinc and Iodine and Water are mixed together a color is formed in the solution and a release of heat occurs, an exothermic reaction. The color starts out as a reddish brown color, and then, when swirled, becomes a gold yellowish color, and slowly becomes transparent clear at the end of the reaction.
The purpose of this step was to remove (extract) most of the water that has dissolved in the ether layer. 2) The aqueous layer was drained and the solution discarded in the sink. 3) The ether layer was poured out the top of the separatory funnel into a clean, dry Erlenmeyer flask. 4) Several scoops of anhydrous Mg SO4 were added and the solution swirled. The MgSo4 absorbed the last traces of water the ether solution.