Kumari Biswas Chem 106 – 07 October 06, 2014 Menglu Shi Group member: Shemeika McLaren, Jose Suarez, Colleen Shum Lab 3: Redox Arena Redox Arena Lab Part I Observations and Data Observations of starting materials and standards Chemicals | Observations | The Four standards | Granular zinc | Silver-gray irregular solids | Iodine crystals | Purple-black spherical solids, strong smell | Zinc ion and iodine-iodide-triiodide ion in H2O | Red brown liquid | Zinc iodide | Gray white solid powder | Chemicals used for tests | 0.17 M acetic acid | Clear liquid | Mineral oil | Thick clear liquid | Silver nitrate (AgNO3) | Clear liquid | Magnesium turnings | Solid curled metals | 3 M HCl | Clear liquid | Other chemicals
d) The reactions are complete when the bubbles stop forming. e) Zinc, Hydrogen, Copper Challenge What is the chemistry-based reason for this peculiar construction of a penny? Zinc is too reactive to for the coin to be totally made out of zinc. The copper is not as reactive and is a protective
We resulted that lead, silver, and copper are the strongest oxidizing agents, and that magnesium and zinc are the weak oxidizing agents. The strong oxidizing agent oxidized the weak oxidizing agent and in turn the strong oxidizing agent got reduced while oxidizing the weak agent. When a reaction occurred, the solid metal reduced the ion, and in turn made it the more reactive metal. In part two we used a solvent extraction technique to derive an activity series for the halogens. With the use of this technique we placed chlorine, bromine, and iodine into solutions containing chloride, bromide, and iodide.
Alkali Metals- Group 1 (IA) The alkali metals make up Group 1 of the periodic table. This family consists of the elements lithium, sodium, potassium, rubidium, cesium, and francium (Li, Na, K, Rb, Cs, and Fr, respectively). Group one elements share common characteristics. They are all soft, silver metals. Due to their low ionization energy, these metals have low melting points and are highly reactive.
Use your answers to Questions 1 and 2 to explain how a water-insoluble organic acid might be freed of non-acidic impurities. Water-insoluble organic acid can be freed of non-acidic impurities by adding strong base into it during fractional distillation. The water-insoluble organic acid will react with the strong to produce an ionic salt which is soluble in water. On the other hand, water-insoluble organic acid which are slightly soluble in water can be extracted by aqueous base from solution in an organic solvent. The fact that organic acid are weak acids and only partially dissociates in
The substance dissolves in water but not in alcohol, is transparent when dissolved in water, is electrically conductive when dissolved in water, dries white, and has a high melting point. Out of the four compounds we received to test, according to the data we collected, sodium carbonate was the one that would work the best as a fixative for the glaze. In the experiment we conducted you will notice that the independent variables were the different compounds, while the dependent variables were the results to the criteria that had to be met. Also, during our research, we found that sodium chloride and sodium carbonate worked better than sucrose and salicylic acid because they have ionic bonds. These conditions are more suitable for ionic bonds.
When in flame it produces gas rapidly and bubbles. Liquid turns into gas quickly. When liquid disappears solution (now a solid) turns white | 4 | A Initial temperature is 15 degrees Celsius and the final temperature is 17 degrees Celsius. BThe blue hydrated copper sulphate turned white, evidence of condensation of a clear liquid present on the inside of the test tube.C concentrated sulphuric acid turns black on paper towel and is clear on the white cottonD Carbon pillar grows cause of air bubbles, it is brittle, it is both corrosive with a hole and there is evidence of carbon produced | 5 | No temperature change and iodine brown/yellow gas produced | Properties of Sulphuric acid results table Aim: To investigate and observe the properties of sulphuric acid through five different experiments where we will determine its extent of ionisation in aqueous solution, reaction of sulfate ions, action as a strong acid, affinity for water and action as an oxidising agent. Background: Sulfuric acid (H2SO4) is a diprotic acid (can donate 2 protons to a base).
Properties of Compounds Purpose: The purpose of this lab was to determine whether an unknown substance was ionic or covalent compound based on some common characteristic such as melting point, solubility, and conductivity. Data: Table 1: Properties of Compounds Compound Physical appearance Melting point Solubility in water Solubility on cyclohexane Conducts electricity? H2O Clear liquid Nearly none None Cyclohexane Clear liquid None A Small crystals >277 °C Tube1: Partially Tube 2: Nearly none Strongly B White powder >277 °C Tube 3: Nearly none Tube 4: Nearly none Strongly C White crystals 187.06 °C Tube 5: Freely Tube 6: Partially None D Crystals 195.31 °C Tube 7: Nearly none Tube 8: Freely None E Small crystals >277 °C Tube 9: Freely Tube 10: Nearly none Strongly Results: After dipping the conductivity apparatus into each of the tubes that contained water, the compounds that conducted electricity were Compounds A, B and E. When a compound mixed with water conducts electricity it is considered an ionic compound. If a compound is not ionic when it dissolved in water it will not form ions, but will instead break up into molecules. Therefore compounds H2O, cyclohexane, C, and D are molecular compounds.
Name: Amandeep Sandhu |Date: 06/16/2012 | | |Exp 4: Physical & Chemical Properties |Lab Section: | Data Table: Substance |Color |Odor |Effect of Heat |Cold H2O |Hot H2O |Litmus Test |Dilute HCl |Dilute NaOH | |Mg |Silver Or Gray |Odorless |Forms a white powder |MgO+H2 |Mg(OH2)+H2 |Blue |MgCL2+H2 |MgOH+Na | |Cu | Orange |Odorless |Glows dull red |NO REACTION |Mg(OH2)+H2 |Blue |No Reaction |Cu(OH)2+Na | |Zn | Bluish-white |Odorless |Turns yellow |No Reaction |ZnO+H2 |Blue |ZnCL2+H2 |Na+Zn(OH)2 | |MgO | White |Odorless | |Mg(OH)2) |Mg(OH)2) |Blue |MgCL2+H2O |MgOH+NaO | |CuCO3 | Green |Odorless |Forms Copper Oxide & Carbon dioxide gas |CO2+Ca(OH) 2 |CO2+Ca(OH) 2 |Green |CuCl2+H2CO3 |CuOH+NaCO3 | |Cu(NO3)2 | Blue crystals |Slight | | |Cu2+NO3+H2O |Blue |CuCl2+2HNO3 |CuOh2+NaNO3 | |NaCl |White |Odorless |Melts & become clear liquid | |Na+Cl+H2O |No Color |No Reaction |NaCl+NaOH | | Conclusion: The purpose for this experiment was to combine different chemicals to see if a physical or a chemical change occurred. A physical change happens when the substance changes in appearance yet maintains its physical and chemical properties. A chemical change occurs when a different substance forms with newly formed physical and chemical properties. The first substance was magnesium. Before it was heated, it was a shiny silver strip.
* To improve mathematical skills. The stability constants of the tri-iodide ion was found to be Introduction: Non-polar octamethylcyclorasiloxame, volasil 244, and polar potassium iodide are mixed together and the iodide distribution between them was examined. Volasil 244 is a source of I2, potassium iodide is a source of I- and in equilibrium they are I2 + I- I3-. The equilibrium or stability constant is denoted by [I3-]/[I2][I-]. I2 is the only species that is undergoing distribution.