2Al + Fe2O3 ( Al2O3 + 2Fe (26.98) ( 159.7) (101.96) 124 601 80 b. Al c. 234.3 d. 234 e. 34.1% 1c. A strip of zinc metal with a mass of 2.0g undergoes single displacement reaction with an aqueous solution containing 2.5g of silver(I) nitrate A. Write a balance equation for the above reaction B. Which of the 2 reactants is the limiting reagent? C. Calculate the mass of zinc (II) nitrate formed D. How much excess reagent is left at the end of the reaction?
a. melting of lead b. dissolving sugar in water c. tarnishing of silver d. crushing of stone e. dropping a penny into a glass of water | | Save Answer | | 5. (Points: 5.4) | | Which one of the following has the element name and symbol correctly matched? a. P, potassium b. C, copper c. Mg, manganese d. Ag, silver e. Sn, silicon | | Save Answer | | 6. (Points: 5.4) | | For which of the following can the composition vary?
We determined that the mass of zinc necessary to completely react with the copper (II) ions in the solution was 1.308g. We added an excess of 0.050 to make sure the copper completely reacted. 1.358g of zinc was then added to the solution. The solution with the zinc was heated and stirred until it was colorless, showing that the reaction was done. Hydrochloric acid was then added to the solution until the bubbles stopped in order to completely get rid of all of the zinc.
Zinc ion and Iodine-iodide-triodide ion in water: It was a liquid solution in a bottle, it was very dark orange-brown color. Solid Zinc Iodide: A very white powdery substance that had several clumps within it. It was also very dry in nature. Mass Table Substance Amount of Mass Measured for Actual Mass Granular Zinc 2.0 grams 1.9 grams Iodine Crystals 2.0 grams 2.1 grams Observation of Reaction Shown below and Included within the lab notes on pages 12 and on page 14. Placing Acetic Acid in Zinc and Iodine test tube After placing the Acetic Acid in a normally unreactive test tube containing Zinc and Iodine, the solution changed to a more orange and then to a more red-brown color.
Results APPEARANCES OF MATERIALS USED Substance Physical Appearance Zinc Carbonate White; powderish Calcium Hydroxide White; powderish; like zinc carbonate 3 M HCL Clear liquid, resembles water 20 mesh granular zinc Grey, metallic, shiny 3% hydrogen peroxide Clear liquid; resembles water Manganese dioxide Very dark grey, black and powdery Copper sulfate Blue, crystalline in structure. Sky blue Zinc iodide Very dark purple, shiny and crystalline in structure 0.1 M acetic acid Clear liquid, resembles water Zinc oxide Very white powdery substance RAW RESULTS Data Specifided (Page 112 CRC handbook) Raw data Volume of Gas Collection Bottle (Average of 3 Trials) 14.04mL Mass of boiling tube (empty) 41.57g Mass of boiling tube with zinc carbonate 43.42g Mass of zinc carbonate 1.75g Volume of water in gas collection bottle after reaction 78.5mL Volume of gas product collected 185.2mL Mass of solid product with boiling tube after reaction 1.11g QUALITATIVE TEST RESULTS Group # Test Observation: Standard Positive/Negative Observation: Experimental Positive/Negative 1 H2 HCL + Zinc bubbling + flaming stick POP! + + flaming splint no POP - 2 CO2 Turned cloudy + Negated from experiment Negated from experiment 3 O2 MgO2 + Hydrogen Peroxide bubbling. Glow stick re-ignited + + wooden splint; glowing stick went out - 4 H2) Added 1 pea size CuSulfate + 1 drop of deionized water; blue, positive + Copper sulfate did not change color when put into wet filter paper - 5 Zn (OH)2 Zinc iodide + 3mL H2O Clear suspension + Visual inspection; cloudy. Acid test= solid + 3M Acetic acid cloudy + 6 ZnO ZnO + Heat yellow Zn Cooled White + ZnCO3 + heat yellow solid.
This is a neutralization reaction between a strong acid and strong base. Therefore the heat of reaction (∆H2) is called as the heat of neutralization of HCl and NaOH solutions. The ∆H2 calculated from this experiment is -6.6944KJ/mol. This is because the enthalpy changes when one mole of H+ ions from an acid (HCl) reacts with one mole of OH- from an alkali (NaOH) to form one mole of water molecules under the stated conditions of the experiment. In the final reaction of the experiment (Part C), solid NaOH will react with an aqueous solution of HCl.
(c) Calculate the mass of water formed when 20 g of methane undergoes complete combustion. 6 Deduce the empirical formulae of the following: Moles and empirical formulae 1 Calculate the molar mass of these compounds. (Relative atomic masses H = 1; N = 14; O = 16; Mg = 24; S = 32; Ca = 40; K =39; Cr = 52; Fe = 56.) (a) calcium ethanoate, Ca(CH3CO2)2 (b) chromium sulfate Cr2(SO4)3 (c) magnesium hydroxide, Mg(OH)2 (d) potassium cyanoferrate(III), K3Fe(CN)6 2 When 2.4 g of magnesium
| The sugar will start to become hard again at room temperature. | Sodium Carbonate and Hydrochloric acid | The sodium carbonate is a white powder and is not in crystal form. The hydrochloric acid is a clear non-viscous liquid. | The mixture will start to bubble vigorously and release a gas. | Most of the mixture will evaporate leaving only a small amount in the test tube.
In the nitration of benzoic acid, the mixture of HNO3 plus H2SO4 and benzoic acid dissolved in H2SO4 was combined. Combining HNO3 and H2SO4 is an acid-base reaction which will be shown in the reactions to be shown. During the dissolution of benzoic acid solids, some unexpected reactions visibly occurred. White slimy and sticky ppts start to form which was unexpected from the reaction mixture. Both mixtures are placed in an ice bath and when it was combined, the temperature of 0-10C was maintained.
Laboratory Report for Experiment #5 Titration of Acids and Bases 1 Acids and Bases – Volumetric Analysis I. Introduction The purpose of this experiment was to understand the basic techniques of titration, solution preparation and volumetric analysis. A fundamental property of aqueous solutions is the determination of hydronium ion [H3O+] concentration. The pH of a solution mathematically describes the hydrogen ion concentration [H+], where: (p37) pH = -log [H+] A strong acid or base in one which is completely (100%) ionized in dilute aqueous solution. A solution containing 0.1 M of hydronium ions (p37) HNO3(aq) -> H3O+ (aq) + II.