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
| 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.
What are the identities of the substances found after electrolysis and heating? The identities of the substances found were Iodine, Iodide ion (I-), Triodide ion(I3-), Zinc metal and Zinc ion(Zn2+) Post Lab questions: 1. What did this experiment convincingly show about the composition of the white solid? I put that the experiment showed us the white substance was comprised of Zinc ions and iodide ions, and that the two ions and be separated back into their respective elements 2. During the electrolysis, a gray solid formed on the negative wire of the battery and the dark red solution formed at the positive wire of the batter.
Through our identification tests, we identified the gray solid to be zinc granules, the colored solution to be zinc ion and iodine-iodide-triiodide ion in water and the white solid to be solid zinc iodide. These identifications compared well with two other groups data. Ismat Zerin and Savita’s group also identified these substances to also be zinc granule, zinc ion and iodine-iodide-triiodide ion in water, and zinc iodide. Even though our conclusion was the same, our identification results did differ to some extent. 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.
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.
The simple addition of water to FeSO4 will not lead to the formation of FeSO4•7H2O. Determination of the number of molecules of water in a hydrate. If you do not know how many molecules of water are in one molecule of hydrate and want to find this out, it can be done by measuring the masses of the hydrate and anhydrous compound formed after the heating. For example, let’s assume that we do not know how many water molecules are attached to BaCl2. Let’s call this number X.
This technique prevents the product to contact other reactants, and leave the heating environment which might cause side reactions. The removal of the product also helps to shift the equilibrium position of the incomplete reaction to the right hand side, and prevents backwards reaction, resulting in an increased yield of products. This experiment also introduces the idea of azeotrope. An azeotrope is a mixture of two or more pure compounds in such a ratio that its composition cannot be changed by simple distillation. This is because when an azeotrope is boiled, the resulting vapour has the same ratio of constituents as the original mixture of liquids.
Figure 2 shows a circuit with a resistor R = 1.0 × 103 Ω, and a battery with potential difference of VB = 5.0V . (a) Solve the circuit in Figure 2. That is, find all unknown currents, voltages, and resistances. (b) What is the direction of the current? Note: I want the direction of the conventional current.
Questions Place one small scoop of copper chloride crystals onto a piece of Al foil. 1) What do you observe happening? 2) What is the electrochemical potential difference between copper and aluminum? Do you expect a reaction to occur? If so, write a balanced equation for it.
Jose Flores 6th period 1-27-14 LAB REPORT Introduction: A substance can conduct an electrical current if it is made of positively charged and negatively charged particles that are free to move about and is called a conductor. The purpose is to figure out conductivity of substances and to check which one conducts electricity. The hypothesis is that sucrose would be the only one that could not conduct out of the other six solutions. Materials: The materials used in this lab where six solutions , napkins, 2 pairs of gloves, 2 cups (1 cup with distilled water and 1 cup with solid NaCI) and a conductivity meter. The six solutions are sodium chloride, hydrochloric acid, sodium hydroxide, acetic acid, ammonia and sucrose.