(d) What evidence suggests that nitrate compounds are soluble in water? (e) Write the chemical formula for each precipitate that formed. Apply and Extend (f) Write a balanced chemical equation for each precipitation reaction that occurred. (g) Why is it necessary to use distilled water to prepare the solutions used in this investigation? (h) "Hard" water contains a high concentration of calcium ions.
Chemistry: Molarity and Stoichiometry Directions: Using the definition of molarity, the given balanced equations, and stoichiometry, solve the following problems. Please submit your work via the link provided. 1. Calcium hydroxide (“slaked lime”) and sulfuric acid react to produce calcium sulfate and water according to the following balanced equation: Ca(OH)2(aq) + H2SO4(aq) ⋄ CaSO4(s) + 2 H2O(l) a. How many liters of 0.2 M calcium hydroxide do you need in order to have 6.0 moles of calcium hydroxide?
The change in enthalpy relies on the concentration of the salt solution, because different concentrations will produce different enthalpies. There is an equation to determine how much of this heat energy is lost or gained when a reaction is performed. Q = c m (T1-T2) Where: q is the energy in Joules C is the heat capacity, measured in joules per gram per degree Celsius M is the mass of the solution, measured in grams J is the joules G is the grams of water T is the temperature ΔH=ΔE + PΔV = (q p +w) – w = q p Procedure: 1. Follow instructions 1-9 in Appendix A-1 to initialize the MeasureNet workstation. a.
Halides Lab: Background information: Halide ions are reactive and useful. Salts are positively charged ions (metals) combined with any negative ions (nonmetal), and when placed in a solution (water) it separates into the cations and anions that made it up. The Purpose of this lab is to find out how the Halides react with the indicators, and to determine the identity of the two unknown solutions (A and B). Color of solutions prior to experiment: NaF | NaCI | KBr | KI | Unknown A | Unknown B | clear | clear | clear | clear | clear | clear | Color of indicator prior to experiment: 5% Bleach (NaOCI) | 0.2 M Na2S2O3 | 0.1 M AgNO3 | 0.5 M Ca(NO3)2 | clear | clear | clear | clear | Halide solutions | NaF | NaCI | KBr | KI | unknown A | unknown B | Test 1: Ca(NO3)2 | Cloudy White (Nothing) | Clear | Nothing | light yellow (Nothing) | Nothing | Nothing | Test 2, Part A: AgNO3 | clear (Nothing) | Milky White | Gold (Cloudy yellow) | milky green (Cloudy yellow) | turned white, film developed on top layer | Milky | Test 2, Part B: add Na2S2O3 to test tube from part A | Dark Orange/brown | Clear | Dark Gold(precipitate yellow then clear) | milky green (no change) | white precipitation, settled on bottom | Milky | Test 3: NaOCI (Bleach) | Clear (Nothing) | Nothing | Nothing | Orange (Clear) | Nothing | Orange | Unknown A is identified as NaCI (Sodium Chloride), because in test#1 the solution turned a cloudy white color when Ca(NO3)2 (Calcium nitrate) was added. In the first part of test#2, when AgNO3 (Silver nitrate) is added, the solution turned white, with a thin layer of film developing on the surface.
William Flores-Paz Monitoring Acid-Base Titrations with a pH meter October 30, 2013 Introduction The purpose of this experiment was to record the volume of HCl and acetic acid with a NaOH with a known molarity. This data would allow us to create a graph so we could compare the two titration curves. We would then use these curves to calculate the unknown molarities. HCl + NaOH >H2O + NaCl This equation shows the relationship between the acid and the base then the reaction goes forward and they are titrated creating salt and water. This particular reaction is a strong acid and a strong base which means that when the reaction reaches the equivalence point, the moles of the acid and the base are equal and the solution is neutral so the pH should be around 7.0 depending on the final volume of each solution.
White precipitate shows the presence of chloride (Cl-). Chloride anion equation: HCl(aq) + AgNO3 (aq) → HNO3 (aq) + AgCl(s). The nitrate anion test involves cooling a mixture containing 1 mL of test solution and 3mL 18M H2SO4. 2mL is poured down the inner test tube side and the presence of a brown ring shows nitrate (NO3-) to be present. The carbonate anion test mixes 1 mL of test solution and drops of 6M HCl.
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.
Let’s call this number X. Then the structural formula of BaCl2 hydrate can be written as BaCl2•XH2O. The reaction of dehydration is |BaCl2•XH2O ( BaCl2 + XH2O |(5) | According to the stoichiometry of the reaction (5) |[pic] |(6) | Where N1 is the number of moles of BaCl2 formed in the reaction (5) and N2 is the number of moles of water lost in the reaction (5). To find out N1 you need to divide the mass of BaCl2 after the reaction by its molar mass. To find out N2 you have to determine the mass of water produced in the reaction.
Introduction High performance liquid chromatography (HPLC) is used to separate compounds in a sample, identify compounds and can even be used to deduce the relative amounts of different compounds in a mixture. HPLC works under the same principle as thin layer chromatography using both a stationary and mobile phase. The mobile phase carries the mixture across the stationary phase which is used to separate the compounds. Although in HPLC mobile phase is tailor made to suit the polarity of the analytes. The mobile phase used in this particular experiment was Methanol and 0.1M sodium dihydrogen phosphate at a ratio of 30:70 and a pH of 4.5, slightly acidic.
,, II I Quantitative Measurements of the Solute Since the solute is the species involved in chemical transformations, our goal will be the determination ot"the number of moles of solute in a particular solution. To be definitive, you want to carry out a reaction that involves zinc iodide. Instead of getting the zinc iodide in the solid state, you go in the .lab and there is a flask that contains zinc iodide diss91ved in water (in the solution state). What might the label on the flask say that will tell you how much iodide there is in the water? · There are numerous measures of the amount of solute in solvent.