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?
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.
Determining the Concentration of a Solution: Beer’s Law Purpose: The purpose of this lab was to measure absorbance value of standard solutions. And to find the relationship between absorbance and concentration. Then determine the concentration and the formula of the unknown CO(NO3)2*nH2O solution. Introduction: The reason we conducted this experiment was to determine the concentration and formula of an unknown solution. We used a calorimeter to monitor the light received by the photocell to determine the absorbance of different concentrations of cobalt chloride hexahydrate.
By recording the amount of silver nitrate (AgNO3) is used, the amount of the chloride used is figured. An indicator is used to help determine when the reaction is complete. The indicator used in this experiment is potassium chromate (K2CrO4). The recorded volume of silver nitrate (AgNO3) used is then used to determine the molarity of the silver chloride (AgCl) created. Moles of AgCl = (Volume of AgNO3 added) × (Molarity of AgNO3) Using the molarity of the silver chloride (AgCl) and the atomic weight of the chloride (35.4527), the weight of the chloride from the original unknown chloride salt sample.
EXPERIMENTAL DETERMINATION OF AVAGADRO NUMBER Purpose The objective is to make an experimental measurement of Avogadro's number. Introduction A mole can be defined as the gram formula mass of a substance or the atomic mass of an element in grams. In this experiment, electron flow (amperage or current) and time are measured in order to obtain the number of electrons passing through the electrochemical cell. The number of atoms in a weighed sample is related to electron flow to calculate Avogadro's number. In this electrolytic cell both electrodes are copper and the electrolyte is 0.5 M H2SO4.
The indicator Phenolphthalein was the substance used to signal when the titration reached the point at which the reactants are stoichiometrically equal as defined by the balance reaction equation. Phenolphthalein is a chemical compound with the formula C₂₀H₁₄O₄ and is often written as "HIn" or "phph" in shorthand notation. Often used in titrations, it turns colorless in acidic solutions and pink in basic solutions. Sodium hydroxide or Hydrochloric acid would not have been as effective or accurate because they would have reacted with the water vapor from the air. In this lab setup, graduated cylinders or beakers were not used.
Create reactions with anion placeholders for copper compound and Zinc. If the copper is cuprous, or Cu+1, the reaction is: 2Cu+1(A-1) (aq)+ Zn+2(s) Zn+2(A-1)2 (aq)+ 2Cu+1(s) (A= anion) If the copper is cupric, or Cu+2, the reaction is: Cu+2(A-1)2 (aq) + Zn+2(s) Zn+2(A-1)2 (aq) + Cu+2(s) Calculate the grams of Zinc needed for the reaction if copper compound is cuprous (+1) or cupric (+2). If the Copper is Cuprous: 2Cu+1(A-1) (aq) + Zn+2 (s) Zn+2(A-1)2 (aq) + 2Cu+1(s) Grams of Zn = 1 gram of Cu(A) The amount of Cu(A) that will be used. 1 mol of Cu(A) Divided by the molar mass of Cu(A) 170.49 grams of Cu(A) as given by the instructor. 1 mol of Zn Multiplied by the mole ratio of Zn to Cu(A) 2 mol of Cu(A) in the reaction.
The rate law for this reaction is rate = k[acetone]m[H+]n[I2]p where k is the rate constant for the reaction and m, n, and p are the orders of the reaction with respect to acetone, hydrogen ions (acid), and iodine, respectively. Although orders of reaction can be any value, for this lab we will be looking only for integer values for the orders of reaction (0, 1, 2 are acceptable but not 0.5, 1.3, etc.) The rate of the reaction can also be expressed as the change in the concentration of a reactant divided by the time interval: rate = - Δ[ I 2 ] Δt The iodination of acetone is easily investigated because iodine (I2) has a deep yellow/brown color. As the acetone is iodinated and the iodine converted to the iodide anion, this color will disappear, allowing the rate of the reaction to be easily monitored. We can study the rate of this reaction by simply making I2 the limiting reactant in a large excess of acetone and H+ ion.
Chose and Obtain Sulfate Solution will form aqueous compound as sulfate when combined with anything is aqueous · Is an anion 3. Chose and Obtain Nitrate Is an anion · Need another anion to test and see if order of reactivity is correct for each anion Solution will always form an aqueous compound according to Alchem Table 4. Chose and Obtain Copper Used by different lab partners whose data was observed Carrying Out The Reactions & Collecting Data How Why 5.Place 10ml of water in a test tube Done so aqueous solution may be made 6. Take magnesium nitrate and place 3 drops into test tube with water Done to have one part of the reaction 7. Repeat step 5 and 6 but replace magnesium with zinc Done so 2 metals can be tested at the same time 8.
At 50C our results indicated a solubility of 89 g/100mL of H2O which was close to the known solubility of 80 g/100mL. Introduction: When a salt, such as potassium nitrate or sodium chloride, is placed in water a dissolving reaction will occur. At first, the positive and negative ions of the salt compound are only attracted to each other. In order for the salt to dissolve, these bonds must be broken so that the ions disassociate from each other. In the water molecules, hydrogen is slightly positive and oxygen slightly negative so they are attracted to ions of the opposite charge, known as dipole attraction.