Determine the Solubility-Product Constant for a Sparingly Soluble Salt Abstract: The Solubility-Product Constant of a sparingly soluble salt was determined by using a calibration curve to determine the connection between the concentration and absorbance (y=1629.8x+0.0117). After the compounds had been prepared, the absorbance was measured using a spectrophotometer. The (CrO42-) ion could be used to calculate the solubility-product constant because of the close stoichiometric association between the two. The average Ksp of Ag2CrO4 was 1.59x10-10 M. Introduction: Many elements come into the determination of the solubility-product constant for a sparingly soluble salt. One of these elements is the study of spectroscopy. Spectroscopy is defined …show more content…
Ksp is known as an equilibrium constant of the solubility product, but Kc is used for the equilibrium constant of the reaction. Ksp is a representation of the level at which a soluble solution can dissolve. The greater the solubility of a substance, the higher the Ksp. The constant of the value Ksp tells the degree where the compound separates in water. Some experimental techniques that are used to determine Ksp for a sparingly soluble salt are titration, spectrophotometry, and gravimetry. Ksp value shows the degree at which a solution is separated in water. When solving for Ksp it is important to take the concentrations of the products and multiply them. In the experiment when determining the Ksp of Ag2CrO4. We need to make the equilibrium reaction for the disintegration of Ag2CrO4. For instance the equilibrium equation …show more content…
The first Ksp ended up to 1.74 x 10-10 M. The second value was calculated to be 1.46 x 10-10. Lastly the third value ended up being 1.57 x 10-10. These three values ended up having an average Ksp of Ag2CrO4 was 1.59 x 10-10. Discussion/Conclusion: The purpose of this lab was to determine the solubility-product constant value of Ag2CrO4. The average value of Ksp was 1.59x10-10, but the value that was accepted for the solubility- product constant was 1.12x10-12. This shows that the percent error value of Ksp was 40.2 %. Percentage of error is used to help determine if the answer that was obtained is close to the value that was supposed to be found. Although when looking at what was received for the percent error, it shows that during the experiment there were some errors that had occurred. Some possible errors that could have happened while the experiment was taking place include miscalculating values, inaccurate measurements, and the equipment could have been setup
To begin, the solubility of the unknown compound in water was tested. If the compound is soluble in water, it can be inferred that it is either a polar covalent or ionic compound.
Now, I used the balanced chemical equation to find the number of moles of AgNO3 that reacted with Na2CO3. From the chemical equation, I saw that 2 moles of AgNO3 react with 1 mole of Na2CO3. (2 AgNO3 + 1 Na2CO3 -> 1 Ag2CO3 + 2 NaNO3). moles of AgNO3 = (moles of Na2CO3) / 0.5 moles of AgNO3 = 0.0141 mol / 0.5 moles of AgNO3 = 0.00282 mol Finally, I found the molarity of the silver nitrate solution.
The average concentration of my unknown Al3+ solution (#41) was 0.02372 0.00016 mol/ L. My %RSD was 0.67%, which I would say is very good. This means my precision relative to my average was very good. When calculating the mass of the precipitate, my Trial #1 and #2 were both 0.271X, with Trial #3 being 0.27XX.
By finding where the first K is equal to 1 and seeing what the Q value is at this given point, K can be solved. As said above when H equals 1 the Q value is the same as the K value. The K value was calculated to be 4.7. In the second method for solving for K, use the values calculated for the variables Q, K, and n and plug into Equation 1. By doing this the calculated value was 4.645.
Pure ASA crystals are isolated from the solution with a Hirsch Funnel that was used with a filter. The melting point of the pure ASA crystals were calculated in order to calculate of absorbance. Iron (III) salicylate dianion must contain the acidified solution Fe3+ in order to measure the absorbance values. The level of the impurity can
Title: Solubility equilibrium Objectives: To study the thermodynamics of solubility of naphthalene in diphenylamine Introduction: Phase equilibrium is a state of balance which rate of transfer of matter or heat from one phase to the other is equal to the rate of transfer in the reverse direction at equilibrium. The driving force for a phase change is the minimization of free energy and causing material or heat transfer are balanced at equilibrium. The equilibrium phase is always
The Stoichiometry and math calculations are done based of off exactly 3.00g which means that if the student does not have exactly 3.00g then the results will be flawed. Another plausible source of error in the experiment can be that the precipitate was not fully dry when we took the mass
3. In this experiment, the percent yield was 90%. This number implies that there was little error in this experiment. However, this result could have been caused by certain external factors.
Analyzing the Identity of a Metal Carbonate using Stoichiometry Introduction: In this lab, I determined the identity of an unknown carbonate. Based off of the mass percentage of this unknown carbonate, I was able to determine whether it was sodium carbonate, potassium carbonate, or rubidium carbonate. The purpose of this lab was to determine the mass percentage of said unknown carbonate in the given precipitate. The method used to determine this was called gravimetric analysis.
The actual data is the result on our experiment vs theoretical, which is based on the calculations above. I have also learned to pay more attention to draining out all of the product completely before continuing to test the experiment, as any small drop of contaminant can veer our results into a different
1. Aims a) To find the molar absorptivity of salicylic acid by plotting a graph of absorbance against the concentration of salicylic acid, using the standard solution. b) To find the concentration of aspirin at the various time intervals using the molar absorptivity value in the previous part, initial concentration of aspirin and the concentration of salicylic acid obtained from the decomposition of the aspirin pill. c) Lastly, to calculate the rate constant of the decomposition of aspirin by plotting a graph of ln[aspirin] against time and making use of the gradient of the best fitted line along with the standard deviation. 2.Data
The rate of elution affects the band shape of a chromatographic peak. It is also affected by the different paths available to solute molecules as they travel between particles of stationary phase. The reason for band broadening was well explained by Van Deemter equation for plate height HETP =
CHAPTER 6 RESULTS AND DISCUSSION 6.1. INTRODUCTION The experiment gave the knowledge about various things and various factors played their significance role in it. The experiment stated the Chromium removal and for that we had drawn a calibration curve (graph 6.1) between Absorbance on y axis and concentration on x axis through the table 6.1 as given below. To make calibration curve, we needed the absorbance of the Chromium solution which we got from atomic absorption spectrophotometer (AAS).
Practical I: Acid-base equilibrium & pH of solutions Aims/Objectives: 1. To determine the pH range where the indicator changes colour. 2. To identify the suitable indicators for different titrations. 3.
Experiment 5: Study of Solubility Equilibrium Aim To determine the solubility product constant Ksp of a sparingly soluble salt potassium hydrogen tartrate (KHC4H4O6) in water To calculate the change in enthalpy (ΔH° reaction) and entropy (ΔS° reaction) of the reaction Results and Discussion The dissociation reaction of potassium hydrogen tartrate (KHC4H4O6) in water can be written as: KHC4H4O6 (aq) ⇆ K+ (aq) HC4H4O6- (aq) Determination of Ksp at 284 K The expression of its solubility product constant Ksp is Ksp =