It can also be used to analyze samples taken from the field thus allowing

It can also be used to analyze samples taken from the

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field, as it can affect the dosage of medicine administered to a patient. It can also be used to analyze samples taken from the field, thus allowing further knowledge of our changing environments. This experiment confirms the validity of titration and its uses in modern science. II. Data and Results a. Data tables and plots i. Table 1. Standardization of NaOH Trial Mass KHP (g) Volume NaOH Solution (ml) [NaOH] (mol/L) 1 0.063 36.30 0.008500 2 0.063 40.60 0.007600 3 0.063 29.60 0.010400 4 0.066 43.20 0.007500 Mean [NaOH] (mol/L) 0.008500 ii. Table 2. Initial Parameters of Titration Volume of Cola (ml) 20 Initial pH 2.46 iii. Table 3. Data for Titration of Cola Volume of titrant (ml) pH pH V (ml) pH/ V Avg. V of titrant (ml) 0.00 2.46 0.0 0 0.00 0.00 0.00 0.98 2.49 0.0 3 0.98 0.03 0.49
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1.98 2.63 0.1 4 1.00 0.14 1.48 2.98 2.63 0.0 0 1.00 0.00 2.48 3.98 2.70 0.0 7 1.00 0.07 3.48 4.98 2.79 0.0 9 1.00 0.09 4.48 5.98 2.86 0.0 7 1.00 0.07 5.48 6.98 2.96 0.1 0 1.00 0.10 6.48 8.08 3.07 0.1 1 1.10 0.10 7.53 9.08 3.18 0.1 1 1.00 0.11 8.58 10.08 3.33 0.1 5 1.00 0.15 9.58 11.08 3.55 0.2 2 1.00 0.22 10.58 12.08 3.86 0.3 1 1.00 0.31 11.58 12.58 4.05 0.1 9 0.50 0.38 12.33 13.08 4.33 0.2 8 0.50 0.56 12.83 13.58 4.81 0.4 8 0.50 0.96 13.33 14.08 5.26 0.4 5 0.50 0.90 13.83 14.58 5.66 0.4 0 0.50 0.80 14.33 14.98 5.84 0.1 8 0.40 0.45 14.78 15.58 6.04 0.2 0 0.60 0.33 15.28 16.08 6.19 0.1 5 0.50 0.30 15.83 16.58 6.31 0.1 2 0.50 0.24 16.33 17.08 6.42 0.1 1 0.50 0.22 16.83 18.08 6.57 0.1 5 1.00 0.15 17.58 19.08 6.72 0.1 5 1.00 0.15 18.58
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20.08 6.84 0.1 2 1.00 0.12 19.58 20.58 6.92 0.0 8 0.50 0.16 20.33 21.08 6.97 0.0 5 0.50 0.10 20.83 21.58 7.05 0.0 8 0.50 0.16 21.33 22.58 7.14 0.0 9 1.00 0.09 22.08 23.58 7.25 0.1 1 1.00 0.11 23.08 24.58 7.37 0.1 2 1.00 0.12 24.08 25.58 7.48 0.1 1 1.00 0.11 25.08 26.58 7.58 0.1 0 1.00 0.10 26.08 27.58 7.75 0.1 7 1.00 0.17 27.08 28.58 7.91 0.1 6 1.00 0.16 28.08 29.58 8.12 0.2 1 1.00 0.21 29.08 30.58 8.36 0.2 4 1.00 0.24 30.08 31.08 8.50 0.1 4 0.50 0.28 30.83 31.58 8.63 0.1 3 0.50 0.26 31.33 32.08 8.76 0.1 3 0.50 0.26 31.83 32.58 8.90 0.1 4 0.50 0.28 32.33 33.08 9.01 0.1 1 0.50 0.22 32.83 33.58 9.13 0.1 2 0.50 0.24 33.33 34.08 9.20 0.0 7 0.50 0.14 33.83 35.08 9.35 0.1 5 1.00 0.15 34.58 36.08 9.48 0.1 3 1.00 0.13 35.58 37.08 9.60 0.1 2 1.00 0.12 36.58
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38.08 9.67 0.0 7 1.00 0.07 37.58 39.08 9.77 0.1 0 1.00 0.10 38.58 40.08 9.82 0.0 5 1.00 0.05 39.58 41.08 9.89 0.0 7 1.00 0.07 40.58 42.08 9.93 0.0 4 1.00 0.04 41.58 43.08 10.00 0.0 7 1.00 0.07 42.58 iv. Plot 1. Titration Curve with Approximate First Derivative
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0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.00 45.00 50.00 0.00 2.00 4.00 6.00 8.00 10.00 12.00 0.00 0.20 0.40 0.60 0.80 1.00 1.20 Average Volume of Titrant (ml) pH Delta pH/D + v. Table 3. Determination of K a Values K Graphical Analysis Literature Values V 1/2 (ml) pK a K a pK a K a K a1 6.67 2.41 3.89E-03 2.12 7.50E-03 K a2 22.46 7.1 7.94E-08 7.21 6.20E-08 K a1 calculated from initial pH 0.0035 b. Sample calculations i. Standardized molarity of “0.01 M” NaOH solution, trial 1 0.063 g KHP 204.2 g / mol = 3.09 × 10 4 mol 0.0363 L = 0.00850 M ii. Initial concentration of phosphoric acid in cola sample [ H 3 PO 4 ] = mol NaOH at equivalence point initial volume = 0.01 M × 0.00667 L 0.02 L = 0.00334 M iii. K a1 calculated non-graphically, from initial pH and [H 3 PO 4 ] [H 3 PO 4 ] = 0.00334 M
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  • pH, Equivalence point, Sodium hydroxide, kA, Cola Drinks, H3PO4

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