History of the United States Penny As you reach into your pocket to find a penny or two you are holding a piece of history. The penny has been an ever-changing part of the United States history. The one - cent coin, known as the penny, was the first currency of any kind to be authorized by the US. The penny’s design has symbolized the patriotism and energizing spirit of the United States, from Liberty to Lincoln. In 1787, it is believed that Benjamin Franklin designed the first penny, called “Fugio”, when the Constitutional Congress authorized the minting of the first currency.
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.
- signs of chemical change = changes the shape and color, creates a gas, distributes heat, Etc. - Chemical Change= Substance is formed into a completely new substance 2. Hypothesis: If the copper is being tested in these metals ( Copper, Magnesium and cupric chloride) then it would be the least reactive out of magnesium and zinc because it is the lowest among the three on the activity series. 3. Experimental Design: - Independent Variable: different types of metals: magnesium, zinc and Copper - Dependent Variable: amount of reactants observed for each metal - Control : The Air -Constants: The amount of chemical solutions, the time the metals were in the chemical solutions and size of each metal during the experiment 4.
Class data: (in grams) *.81 *.75 2.3 *1.72 *1.39 2.37 2.06 *1.03 2.02 2.18 2.3+2.06+2.02+2.37+2.18=10.93 10.93/5= 2.186 Class average mass of zinc in a penny is 2.19g 3. How much (in g) of the penny was made of copper? Mass of penny 2.47g Mass of zinc - .81g =
Comparing and Contrasting: Compare the ratio of moles of iron to moles of copper from the balanced chemical equation to the mole ratio calculated using your data. 8. Evaluating Results: Use the balanced chemical equation to calculate the mass of copper that should have been produced from the sample of iron you used. Use this number and the mass of copper you actually obtained to calculate the percent yield. 9.
So, if we take random values for r2 between 0 and 1 then we will get different values of time intervals in weeks between successive breakdowns. 3. Lost revenue It is given that they charge $0.10 per copy and number of copies sold in one day follows a uniform probability distribution between 2000 and 8000 copies. Therefore, if we chose a random variable r3 whose value is in between 2000 and 8000 then the lost revenue will be 0.1×r3×repair time. By putting different values for r3, we can get a number of lost revenues by simulation method.
To do that we had to count the molar mass (M) of zinc sulfate. Then we multiplied the amount of zinc sulfate in moles with the molar mass. Then the answer was the mass (m) of the zinc sulfate to add in grams. M(ZnSO4) = (65.38 + 32.06 + 4 x 16.00) g/mol = 161.44 g/mol n (ZnSO4) = 0.02 mol M (ZnSO4) = 161.44
0.00079 moles EDTA4- c. 0.00079 moles ZnI2 d. 0.0517 grams of ZnI2 are in the sample e. 0.0517/0.237= 21.8% f. Error Is 6.34% Lab Report: Part 1: In this lab we used the following supplies: * Zinc Iodide * Na2H2EDTA(s) * Calmagite indicator solution * pH 10 buffer solution * 6M Acetic Acid * Unknown Zinc Compound The main purpose for this part of the lab was to determine the amount of zinc ion in a sample of ZnI2 by titration. The two types of zinc: * Zinc iodide made by zinc and iodine * Commercially purchased zinc iodide (the
The table below shows the displacement reactions of some metals with the aqueous solutions of their salts a. Complete the table below b. Write a worded equation for any one reaction |Metal ion solution |Iron (III) nitrate |Magnesium nitrate |Copper (II) sulphate |Zinc sulphate |Lead (II) nitrate
Body 3.1 Metal 3.1.1 Name Gold is a transition metal with the chemical symbol Au, which is derived from the Latin word aurum (Wikipedia, 2007). The illustration included in the appendices section of this report shows the area of the periodic