Experiment 5: Study Of Solubility Equilibrium
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 = [K+] [HC4H4O6¬¬¬] where [K+] and [HC4H4O6] are the concentrations of the dissociated K+ and HC4H4O6 respectively. Since hydrogen tartrate ion behaves as a weak acid, the number of moles of NaOH used in the titration
…show more content…
Determination of ΔH and ΔS
Using the plot of lnKsp versus 1/T, the slope of the best-fit equation and the y-intercept was found. Using van’t Hoff equation, the change in enthalpy ΔH and entropy ΔS of the dissolution reaction was found to be 44 ± 1.3 kJ K-1 mol-1 and 89 ± 4 J K-1 mol-1 respectively.
Using van’t Hoff equation, lnK = - (ΔH°reaction)/RT + (ΔS°reaction)/R where ΔH°reaction and ΔS°reaction ¬are the standard enthalpy and entropy change of the reaction respectively.
From Figure 1, the gradient and y-intercept was obtained as shown in Table 4 in the Appendix.
The enthalpy change and entropy change was then calculated.
Gas constant R = 8.3145 J/mol * K = .008314 kJ/mol * K
Gradient = (ΔH°reaction)/R
Gradient = - (/ R) = -5264.95
Standard deviation of gradient: ± 157.84
ΔH°reaction = - (-5264.95 x .008314) ± (157.84 x .008314) = (43.7727± 1.31) kJ K-1 mol-1
ΔH°reaction = 44 ± 1 kJ K-1 mol-1
Intercept = (ΔS°reaction)/R
Y-intercept = (/ R) = 10.759 ± 0.52219
Standard deviation of Y-intercept = ± 0.52219
ΔS°reaction = (10.759 x 8.314) ± (0.52219 x 8.314) = (89.4 ± 4.34) J K-1
…show more content…
The experimental Ksp at 291.15 K was found to be 7.10 x 10-4 + 5 x 10-6 and compared to the literature value of 3.8 x 10-4. Since ΔH° reaction and ΔS° reaction was assumed to be nearly independent of temperature, the change in enthalpy and entropy of the reaction was found using the gradient and intercept respectively of the linear plot of lnKsp versus the reciprocal of temperature. Using van’t Hoff equation, ΔH° reaction and ΔS° reaction was found to be 44 ± 1.3 kJ K-1 mol-1 and 89 ± 4 J K-1 mol-1
Alka Seltzer Experiment Lab Report
227 Words | 1 PagesOur original question was what is the effect of different types of water on an Alka Seltzer tablet? What we were measuring was which type of water will make the tablet dissolve the quickest. Our hypothesis was the salt water would dissolve it the fastest, then the pond the second, and tap would take the longest. The results ended up being that the tap water would dissolve the tablet the fastest, then the pond water, and the the salt last. Our three controls are the amount of salt, the amount of water, and the size of the tablet.
Procion Red Dye Lab Report
1454 Words | 6 PagesA hot plate was placed under the ring stand. 50 mL of 3.0 M NaOH in a 250 mL beaker and a stir bar was placed in the beaker. The beaker with NaOH was placed on the hot plate and 3.75 grams of NaAlO2*5H2O was placed in the beaker. The temperature probe was placed in the beaker with the solution, not touching the bottom of the beaker. The solution was heated and stirred till the solution dissolved.
6.03 Pre Lab
993 Words | 4 PagesQuestion3: Experiment 3 The unknown acid sample was 1 • Monoprotic Acid Trails Initial NaOH solution (mL) final NaOH solution (mL) The volume of NaOH to titrate the acid (mL) Amount of Unknown Acid sample 1 (g) The moles of the Unknown Acid (mol) Molar mass of the Unknown Acid (g/mol) A 3.38 28.31 24.93 0.150 0.0026 57.69 B 0.18 29.32 29.14 0.175 0.0029
Millsaps College Lab Manual
1232 Words | 5 PagesThe weekly average was not precise due to the values on Tuesday and Thursday being so much higher proportionally compared to Monday and Wednesday (Graph 1 ). Specific heat was also a value which varied based on the accuracy of the execution of the experiment. Different days lead to different amounts of precision and this was due to the random errors. Random errors were mistakes caused by the experimenter. Tuesday had the lowest standard deviation for all the metals (Table 1).
Catalase Lab
1410 Words | 6 PagesThe reaction was repeated 3 times and average rate noted. From these rates a graph was plotted which describes the relationship of the pressure produced and number of drops added. The reaction rates were measured by Kpa/min and were written to 4 figures for precise results. Time was measured by stop watch. Table 4 shows a summary of all the groups which participated in the lab session.
Unknown Solid Acid
1800 Words | 8 PagesThe KHP and the acid samples must be dried, because there would still be extra water which would skew the molarity. The calculated molarity of the NaOH would be lower because there would be extra volume in the solution, but still the same amount of moles of NaOH, so the molarity would be less, and thus, will require more titrant in order to
Correlation Analysis: Nt1310 Unit 6 Assignment 1
908 Words | 4 Pages-.334 Std. Error of Kurtosis .468 .468 The table shows that the in the data set, the GPA variable is a left skewed distribution of -.053 and a left kurtosis of -.811. The final variable indicates that the left skewed distribution stands at -.334 and a left kurtosis of -.334.
Alka Seltzer Lab Report
802 Words | 4 PagesIntroduction: In this assignment, I will be doing two experimentations on examining the impact of temperature on the Alka-Seltzer’s response time. The first experimentation that I will be doing involves some water that is room temperature. The second experimentation that I will be doing involves some water that is very hot. If I want to be able to figure out the impact of the temperature on water, I will have to document the time it will take for the Alka-Seltzer to go into solution.
Mat 540 Final Paper
801 Words | 4 PagesExplorated Rinf=0.90 Calculated Rinf=0.90 10^(-4) 170 0 0 0 0 0 0 15 42.7 42.7 0.2512 -0.3 0.949711638 30 28.8 71.5 0.4206 -0.58 0 60 26.3 97.8 0.5753 -0.93 0 120 43.8 141.6 0.8329 -2.09 0 240 14.8 156.4 0.92 -3.45 0
Unknown Compounds
1027 Words | 5 PagesEach buffer was measured in a 100 mL graduated cylinder and contained in a 40 mL beaker. Once the reading of the buffer was stabilized, the program entered into reading 1. The probe was cleaned with distilled water and dried before being placed into the second buffer for reading 2. Once the second calibration was completed the pH probe was cleaned again. Next the probe was placed into the unknown solution.
Acid Base Neutralization Lab Report
1001 Words | 5 PagesIV. Data and observations Mass of beaker (g) 174.01 Mass of beaker + NaOH pellets (g) 174.54 Mass of NaOH pellets 0.53 TRIAL 1 TRIAL 2 Mass of potassium acid phtalate (KHP) (g) 0.15 0.15 final buret reading (ml) 30.75
Electrolysis In Chemistry Ia
2800 Words | 12 Pagesso when you multiply the 2.9 by 2 it gives you 5.8 cm3 which was my result. As the voltage increases the volume of hydrogen and oxygen increases. The standard deviation when I used 9 volts for hydrogen it was 0.7 + 0.23= 0.93 and 0.7-0.23= 0.47 so the range of values is between 0.47 cm3 to 0.93 cm3. When I used 9 volts for oxygen it was 0.3+0.12=0.42 and 0.3-0.12=0.18 so the range of values is between 0.18 cm3 to 0.42 cm3.
Enthalpy Of Neutralization Lab Report
1054 Words | 5 Pages℃^(-1)×6.40℃±3.1 %=1337.6 J±4.06 % ∆H=(-1337.6 J±4.06 %) /(0.025 mol ±0.16 %)= -53504 J m〖ol〗^(-1)±4.22 % ∆H=-53504 J m〖ol〗^(-1)±4.22 %÷1000=-54 kJ m〖ol〗^(-1)±4.22 % Conclusion and
Benzoic Acid Lab Report
767 Words | 4 PagesIntroduction Solubility is a chemical property that is measured in terms of the maximum amount of solute dissolved in a solvent at equilibrium. The resulting solution is called saturated solution. For example when a sample of sodium chloride solution in water is heated the behavior of the reaction is endothermic obstructing exothermic behavior. Another relationship that can be said about solubility is that the solubility of a solid substance increases as the temperature increases. The solubility of solutes is dependent on temperature.
Math 1280 Unit 4 Assignment
1600 Words | 7 PagesThe variance is 54.916 to 3-decimal places otherwise 54.91635 A short description of solution 21. I made use of the var function as shown below ………………… ……………………………… That is it!
More about Experiment 5: Study Of Solubility Equilibrium
Alka Seltzer Experiment Lab Report
227 Words | 1 PagesProcion Red Dye Lab Report
1454 Words | 6 Pages6.03 Pre Lab
993 Words | 4 PagesMillsaps College Lab Manual
1232 Words | 5 PagesCatalase Lab
1410 Words | 6 PagesUnknown Solid Acid
1800 Words | 8 PagesCorrelation Analysis: Nt1310 Unit 6 Assignment 1
908 Words | 4 PagesAlka Seltzer Lab Report
802 Words | 4 PagesMat 540 Final Paper
801 Words | 4 PagesUnknown Compounds
1027 Words | 5 PagesAcid Base Neutralization Lab Report
1001 Words | 5 PagesElectrolysis In Chemistry Ia
2800 Words | 12 PagesEnthalpy Of Neutralization Lab Report
1054 Words | 5 PagesBenzoic Acid Lab Report
767 Words | 4 PagesMath 1280 Unit 4 Assignment
1600 Words | 7 Pages