Question

can someone help me finish my table? all the inforamtion is there.

molarity of HCL =0.5M

grams of borax = 18.41g

the Relationship between Thermodynamics and Equilibrium 21 Complete the data table for each temperature studied. Beaker Label 42 °C 45 °C 36 ° C 39 °C 33 °C 2EC 138℃-2°C| ーでー 46℃ Temperature reading (C) Absolute temperature (K) 1/T Final buret reading Initial buret reading Volume of HCI Moles of H+ Moles of B Os(OH)2 Molarity of B,Os(OH)2 306.230.2 3112 3IS2 318.2 9ml Кр Graph In Kn versus 1(T Attach vour aranh Borax Solubility: Investigating the Relationship between Thermodynamics and Equilibrium 21 Borax, also known as sodium tetraborate, is a naturally occurring mineral. Powdered borax con- sists of soft crystals that may be dissolved in water, Borax was first discovered in dry lake beds in Tibet as traders traveled the Silk Road. The compound was later mined in California and Nevada and marketed in the late 19th century for its many household uses. Borax is an active ingredient in some detergents and most ant killers. It is also used as a water softener Borax is slightly soluble in cold water but readily soluble in hot water This allows its application as a laundry detergent. The dissolution of borax in water is shown by the foliowing equation. Na2[B,Os(OH)J.8 H20(s)2 Na (aq)+BOs(OH)2(aq) +8 H200) Solubility product constants are used to describe saturated solutions of ionic compounds with relatively low solubility. A saturated solution is in a state of dynamic equilibrium between the dis- solved, dissociated, ionic compound and the undissolved solid. The solubility product constant Kup, for this equation is related to the ion concentrations in the saturated solution as follows. Recall that Ksp is dependent on temperature. Let x signify the BOALOHXis equal to.x, and the concentration of sodium ion is equal to 2x. The solubility product expression then becomes as follows. ya s6(oH) x. In a saturated solution, the concentration of tetraborate ion, The tetraborate ion formed in solution is a weak base and reacts with water according to the following reaction B,Os(OH) (aq) + 5 H200 4 H,BO(aq) +2 OH (aq) The concentration of B,Os(OH) ion in a saturated solution of borax may be determined by titration with a strong acid according to the following equation: BOs(OH) (aq)+ 2 H20(ag) +3 HyO04 H,BO(aq) You can measure the amount of borate ion in solution by titrating with HCP This allows you to determine the solubility of borax at various temperatures. A Kp value for each temperature will be calculated using the equation Kup-4x Thermodynamics and Equilibrium experiment, you will observe the solubility behavior of borax at varying temperature encounter this in your daily life when you notice that sugar dissolves more quickly and to a greater extent in your hot coffee than in a cold beverage. Other compounds such as calcium Your first step is to determine the Kp value. Next, you will be able to use the relationship between the equilibrium constant and the change in standard free energy, AG, to derive thermodynamic quantities Chemical reactions involve transformations in energy as well as transformations in matter. Thermodynamics is the study of the relationship between heat and other forms of energy. The ndicates the amount of heat absorbed or released as a process occurs at constant pressure and under standard conditions. The standard entropy change, AS indicates the change in disorder in the system as a process occurs under standard conditions. In general, a spontaneous process is favored by an increase in disorder and a release of heat. However, in order to determine whether or not a process will occur in the forward direction under specific conditions, both A and AS must be considered. The enthalpy change and the entro- py change for a process are combined in the thermodynamic quantity known as standard free energy change or Gibs free energy, G is negative, the process will occur in the forward direction at the specified temperature. If AG is positive, the process will not occur in the forward direction at that temperature; it will be spontaneous in the reverse direction. If AG is zero, the process is at equilibrium, and there will be no net change in either direction at that temperature. The relationship between the standard free energy change and the equilibrium constant, K, is shown in the following equation. Note that if K is greater than one, then ΔG° is negative, indicating that the process will proceed in the forward direction under the standard conditions. Combination of the relationships AG equation. AH TAS and AGRTInK results in the following Note: Both AH and AS are temperature dependent. However, for the purpose of this exercise, it may be assumed that they do not change substantially with temperature. This introduces a degree of error into the results Rearranging this equation gives the following. RT R A plot of InK versus 1/T should give a straight line with slope equal to -AHIR. Theoretically, the y-intercept of the plot, wherex-0, should be equal to AS R. However, x is 1/T, and there is no y-value for which 1/T- 0. Thus, AS may not be determined directly from the plot Procedure Fill an 800 mL beaker about three-quarters full with distlled water. Place the beaker on a hot plate, and put a large-mouthed graduated pipet into the water You will do a series of five titrations. Label five clean 125 mL Erlenmeyer flasks as 33 °C, 36 °C, 39 ℃ 42 ℃, and 45 °C. Add approximately 5 mL of distilled water to each flask, and place them out of the way Borax Solublity Investigating the Relationship between Thermodynamics and Equilibrium 155 Next, you will prepare a saturated borax solution. Measure-18 grams of borax iInto a 100 m beaker, and add 70 mL of distiled water. Place the mixture on the ho, plate, and sir фсаее ally Monitor the temperature closely when the temperature reaches 65°C·look for solid sat in the beaker If you observe undissolved salt, you have formed a saturated solution. (f all of the brax is completely dissolved at 65 ℃, add more borax to the beaker whie continuing to heat until some of the salt remains undissolved.) Use beaker tongs to remove the saturated solution from the hot plate. Alow the solution to cool. Continue to heat the beaker of water with the pipet When the borax solution has cooled to -45 "C, aliquot and transfer to the appropriately labeled flask Try not to allow any undissolved borax to use the large-mouthed pipet to remove a 5 mL be transferred. Use the same pipet to transfer 5 mL of the warm distillied water into the lask rinses the plpet and prevents the tips from becoming clogged with borax. Record the actual solution temperature to 0.1°C, Repeat this procedure tor each of the five temperatures. After all of the aliquots have been collected, add an additional 20 mL of distilled water as well as 4 drops of bromcresol green to each flask. The solutions will appear light blue in color Buret Buret clamp Ring stand_ FIGURE 21.1 Setting up the buret From Tro, Laboratory Experiments for Chemistry A Molecular Approach 3e. Pearson Education, Inc Set up a buret as shown in Figure 21.1. Rinse the buret several times with disilled water, and then rinse with a small amount of HCI solution. Fill the buret with the HCl solution, and record the concentration of the HCl solution. Record the initial buret reading, and slowly add the acid dropwise. The endpoint is observed when the solution turns from blue to pale yellow. Titrate each borax solution, recording the initial and final buret readings.

Answer 1

Note 1: all calculation is for Temperature = 33^oC

We have

molar mass of Borax = 381.37g mol^-1

moles of Borax = mass of Borax taken / molar mass of Borax

= 18.41g / 381.37g mol^-1

= 0.04827 moles

molarity of Borax solution = moles of Borax/ Volume of solution in L

volume of  Borax solution = 70ml/1000ml L^-1   

= 0.04827 moles / 0.070L

= 0.689M

Now, Ksp = [Na⁺]² [B4O5(OH)₄^2-]

= 4x³

[B4O5(OH)₄^2-] = x = 0.689M

[Na⁺] =2x

so, Ksp = 4 * [ 0.689 ]³ = 1.3083

ln Ksp = ln [1.3083] = 0.2688

Note 2: moles of HCl = volume of HCl used in titration * molarity of HCl

Similer calculation can be done for the other temperature also.

hope this helps!