Task 3 (D4) Choose one primary and one secondary cell and evaluate their use for portable applications. Primary – (silver oxide cells) Zinc-silver oxide cells effectively use the high electrode potential of silver to produce a high energy density that is combined with a flat discharge curve. This is done as silver oxide forms a positive anode for the cell which could also be mixed with little amounts of manganese dioxide. The metallic zinc in the battery powers the negative electrode which is formed into a gel like substance with the electrolyte usually sodium hydroxide or potassium hydroxide. A separator membrane will then be infiltrated between the negative electrode gel and positive electrode preventing them from being mixed together which would make the battery useless if not in place.
This is evident because the substance tested positive for both the acid test and the base test for zinc hydroxide. Observations of the zinc and iodine reaction without acetic acid: After swirling, the solution starts off to be yellow, than changes to orange. During swirling becomes dark brown- reddish. The tube feels warm, which means that the reaction is exothermic. Soon, the dark red changes into black and then eventually lighter and lighter becomes colorless.
Ethan D. Wilhelm September 10, 2012 Chemistry 121 section 8 Friday 9-12 Sarah Gains Unknown Substance Lab Purpose: The purpose of this lab was to identify an unknown substance B by finding enough of its physical properties that we could eliminate all substances it can’t be. We use micro lab to help us find the boiling point, freezing point and mass. Then we tested the solubility of the unknown substance in water, hexane, and Alcohol. With this information we were able to find the identity of the unknown substance B. Procedure: Throughout this lab we were finding the physical properties of substance B.
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.
These cables are cheap and the network interface cards are cheap as well compared to Fiber NIC cards. In that sense UTP cables are most preferred for patch panels and computer connections to the network. They are also the easiest to work with. Shielded-twisted pair is another type of copper cabling. This is used when you need to run cable through an area that has a lot of Electromagnetic Interference.
Prelaboratory preparation: Read pages 1 – 30 and 45 – 54 of the lab text. You may disregard the microscale distillation procedures of TECH 0704. Answer in your laboratory notebook the Safety Quiz on pages 11 – 12 and the Prelab Questions 1, 2a, 2b, 3 -5, pp. 67 - 68. EXPERIMENT: TECH 0704, Distillation, macroscale technique only, simple and fractional: Substitute a mixture of 25 mL ethanol and 25 mL water for the toluene/cyclohexane mixture.
Hareem Qureshi Group 6 Presentation Lab 6: Grand Central Equation Focus Questions: * Zinc Iodide can be gained through more than one method. We experienced making Zinc Iodide through zinc granules and iodine chips first and then we used Barium Iodide and Zinc Sulfate to make the zinc iodide. Chemists should prepare Zinc Iodide from its Elements rather than using double replacement reaction between Barium Iodide and Zinc Sulfate. In comparison to the grand central equation lab, the castle of quantification lab proves several benefits of using just Zinc and Iodine in formation of Zinc Iodide. Zn + I2 ⟶ ZnI2 | BaI2·2H2O +ZnSO4·7H2O⟶ZnI2+BaSO4+9H2O | Zinc used: (2g x $0.0625)=$0.125Iodine used:(3g x $0.1003)=$0.301Material cost for 3.1g of ZnI2 =$0.498Material cost for 10g of ZnI2 = $1.6 | 0.48g of Zinc Sulfate heptahydrate used= $0.01940.62g of Barium Iodide dehydrate used= $0.549Material cost for 0.48g of Zinc Iodide= $0.5684Material cost for 10g of ZnI2 = $11.84 | % Yield from Zn and I2 reaction: 98.6%% Error: 1.39% | % Yield from BaI2·2H2O and ZnSO4·7H2O reaction:103.6%% Error: 3.6% | The data above shows that Zinc Iodide formation through elements is much more efficient than using compounds.
Name: Daniel Voskresenskiy Post-Lab Report Lab Name: 68th & Zinc - Lab #6 Course: CHEM106 LB SEC: 052 Date: March 18, 2013 Lab Partner: Justin Nus Observations of Reactants (Table 1) Chemical 0.17 M Acetic Acid Buffer 10 Unknown Zinc Compound Physical Appearance Aqueous; clear; colorless Aqueous; clear; colorless; not viscous Fine; Powdery; White; Solid Chemical Zinc Iodide (ZnI2) Calmagite NaEDTA Physical Appearance Solid; powder; fine; white Aqueous; brown/red; not viscous; opaque Fine; Powdery; White; Solid Procedure - Preparing a Solution of EDTA Before titration, a titrant must successfully be made - the substance that will react with zinc ion. Purpose: To find out how much zinc is a sample of zinc iodide we will react zinc
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.
Ammara Abid 9/10/14 Chem 106 A Library for Chemists Observations: * The hydrochloric acid and rubbing alcohol look almost exactly identical. If the labels weren’t on it I wouldn’t know what they were. * The mineral oil looks slightly thicker than the alcohol * The zinc shot has a small tiny teardrop shape * Zinc shot: grey color- less shiny than the granular * Zinc powder: has the consistency of flour except it is grey * Zinc Mossy: Big ½ inch pieces of zinc that resembles the zinc shot in color and texture but they are not teardrop shaped * Solid iodine: small circular pieces- black with a dark purple sheen * The solid iodine has an unpleasant smell that resembles bleach Solubility Test: