Lab Experiment # 11 The common ion effect in dissolution and precipitation Equilibria
Introduction:
Dissolution and precipitation reactions are very important chemical reactions because it is applied to many aspects of the industries in medicine, food, water etc. The objectives of this laboratory experiment is to become familiar with dissolution and precipitation equilibria, develop a lab technique suitable for the determination of the solubility for a sparingly soluble salt, Ba(NO3)2 (s) at room temperature and measure the common ion effect in solubility of Ba(NO3)2 (s) in an acidic solution, HNO3 (aq).
Procedure:
In this lab, the evaporation technique was used to determine the solubility of the salt at room temperature in water.
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Conclusion:
From the experiment, it can be seen that the solubility of barium nitrate in water is greater than the solubility of barium nitrate in nitric acid. This is due to the common ion, NO3-, in barium nitrate and nitric acid. The acid dissociation yielded a concentration of this ion already, so the dissociation of this ion from barium nitrate is an additional concentration of the ion. This is called the common ion effect. The experiment took the evaporation technique approach, but there are other ways to carry out this experiment to determine the solubility of barium nitrate. One of such was is by using a specific amount of barium nitrate and dissolving it slowly in water until precipitation occurs. From that the amount that was dissolved will be known by taking the mass of the remaining amount of barium nitrate. This procedure was carried out as well during the lab experiment to test the experiment’s accuracy. From the results, it showed that more barium nitrate was dissolved using the evaporation technique. This is because in the alternate technique, it is hard to determine when the salt begins to precipitate; therefore it is not as accurate as the evaporation
Temperature is known as one of the factors that affect the solubility of a gas in its solvent. Because the enthalpy of solution for gases dissolved in waters is usually
6. The solubility of the solids were tested using a micro tray, by placing them in water and oil to observe their polarity,
AP Chemistry Background The solubility product constant, Ksp, is a particular type of equilibrium constant. The equilibrium is formed when an ionic solid dissolves in water to form a saturated solution. The equilibrium exists between the aqueous ions and the undissolved solid. A saturated solution contains the maximum concentration of ions of the substance that can dissolve at the solutions temperature. A knowledge of the Ksp of a salt is useful, since it allows us to determine the concentration of ions of the compound in a saturated solution. This allows us to control a solution so that precipitation of a compound will not occur, or to find the concentration needed to cause a precipitate to form. The solubility product which will be
Solutions of 6M H2SO4, 6M NH3, 6M HCl, 6M NaOH, and 1.0 M of NaCl, 1M Fe(NO3)3, 1M NiSO4, 1M AgNO3, 1M KSCN, 1M Ba(NO3)2, and 1M Cu(NO3)2 were given in separate test tubes. The color of possible precipitates, ions, acid-base behaviour, odor and solubility rules were conducted and were reported in Table 1. The key information about a mixture of two solutions was
Ionic compounds are soluble in water to a certain point depending on the compound. The level of solubility changes among different compounds. Some ionic compounds can completely dissolve in water and appear to be a homogeneous mixture. Although, some ionic compounds dissolve very little, and could be considered insoluble, since it does not dissolve fully. Depending on the compound, the level of solubility can be high or low. However, ionic compounds could dissolve to a certain degree. If the solution appears to be a heterogeneous mixture, many may assume through visual representation that it may be insoluble. As stated previously, the smallest amount of solubility should be considered. To confirm whether or not the substance is soluble, observe the efficiency when conducting electricity. Due to practical reasons, the slightest solubility could be considered insoluble by people.
If you dissolve a substance such as ordinary table salt (NaCl) in water, the boiling point of the water will increase relative to the boiling point of the pure water. In this assignment, you will dissolve a sample of NaCl in water and then measure the boiling point elevation for the solution.
Because salt dissolves in water, we added water to the salt and sand mixture. Sand is insoluble in water making the sand not dissolve. The mixture containing of sand and salt water was then filtered with filter paper. The filter paper allowed the salt water to pass through because it is a liquid while not allowing sand to pass through because it is a solid. The salt water was then collected in a pre-weighed 250-mL (67.88 gram) beaker while the sand and filter paper was put in a pre-weighed (52.02 gram) 100-mL beaker. The water was then evaporated because we left both beakers to dry overnight.
Purpose of this experiment was to find the amount and percent of water in a hydrated salt. Also, to successfully determine percent error and standard deviation. Hydrated salts are substances that occur naturally who usually contain an amount of water molecules chemically bonded to the compound. A few hydrated salts have weak bonds within the water molecules which allows heat to remove the water molecules creating an anhydrous salt. Hydrated salts that lose water molecules to the atmosphere without a heat source are known as efflorescent. Salts that readily absorb water are called deliquescent. An example of an anhydrous salt would be Magnesium Sulfate or also known as Epsom Salt. Epsom salt separates under heating and becomes
Chemistry 102 is the study of kinetics – equilibrium constant. When it comes to the study of acid-base, equilibrium constant plays an important role that tells how much of the H+ ion will be released into the solution. In this lab, the method of titrimetry was performed to determine the equivalent mass and dissociation constant of an unknown weak monoprotic acid. For a monoprotic acid, it is known that pH = pKa + log (Base/Acid). When a solution has the same amount of conjugate base and bronsted lowry acid, log (Base/Acid) = 0 and pH = pKa. By recording the pH value throughout the titration process and determining the pH at half- equivalence point, the value of Ka can be easily calculated. In this experiment, the standardized NaOH solution has a concentration of 0.09834 M. The satisfactory sample size of known B was 0.2117 g. The average equivalent mass of the unknown sample was found to be 85.01 g, pKa was found to be 4.69, which was also its pH at half-equivalence point and Ka was found to be 2.0439×〖10〗^(-5). The error was 1.255% for equivalent mass and 0.11% for Ka. In other word, the experiment was very precise and accurate; the identity of the unknown sample was determined to be trans-crotonic by the method of titrimetry.
In the experiment, we tested three different water temperatures, boiling water (212*F), room temperature water (68* F), and ice water (40* F), and tested the amount of time it took for the Alka-Seltzer tablet to dissolve. In the boiling water, the Alka-Seltzer tablet dissolved in twenty-four seconds, in the room temperature water, the tablet dissolved in fifty seconds, and in the ice water, the tablet dissolved in one hundred seconds.
In this experiment, hydrochloric acids at different temperatures will be used to observe the effect of temperature in dissolving Alka Seltzer tablets. Four different temperatures as 25 degrees Celsius, 45 degrees Celsius, 65 degrees Celsius, and 85 degrees Celsius will be arranged before the experiment by using a heating pad. 25 degrees Celsius indicates the average room temperature and equal increases will be chosen to observe different responses of Alka seltzer to different temperatures.
As the temperature of water increases, the particles of solid Potassium chloride, KCl, which are absorbing energy from its surrounding, start moving more easily between the solution and its solid state because. According to the second law of thermodynamics, the particles will shift to the more disordered, more highly dispersed solution state. I predict that as the temperature of a KCl and water mixture increases, then the solubility of the KCl will also increase.
Introduction: The purpose of this lab was to study the specific characteristics of cations and anions,
In a test tube, 0.5mL of the sample will be added with 0.5 mL of water and shaken vigorously. Take note for its solubility by parts (0.5mL is one part). Keep adding parts of the solvent until the sample is soluble. If not, add until ten parts of the solvent and determine its solubility. To separate test tubes, water will be replaced with ethanol, chloroform, ether, and acetone as solvents. Same procedures were
In this lab an attempt was made to determine the concentration of a Ba(OH)2 solution by using the conductimetrically determined equivalence point of the reaction between Ba(OH)2 and H2SO4 and by gravimetric determination. The molarity using the equivalence point was determined to be 0.076 M, with a percent error of 24% (actual value was 0.100 M). The molarity using gravimetric determination was 0.0835, an error of 17%. One possible error is the presence of bubbles in the buret. Bubbles would have caused the buret reading to be too high, resulting in a larger equivalence point. Another possible error deals with the colloidal nature of barium hydroxide due to its relatively low solubility. The colloidal barium hydroxide would make it