# Experiment 8

Topics: PH, Acid, Base Pages: 3 (555 words) Published: April 8, 2013
Purpose
This experiment shows how different concentrations of acids and bases in a solution affect its pH level. When acids and bases are combined in a solution, they neutralize each other. This means that depending on the concentration of both acids and bases in a solution, the pH will vary. A neutral pH level is 7; anything below that level is known as an acidic solution, while anything above is known as a basic solution. To find out the pH, the solutions will be diluted and tested with different concentrations.

Experimental Procedure

Dillon, Stephanie. “Reactions in Aqueous Solutions: Strong Acids and Bases” Laboratory Manual. Pearson Publishing 2012, pp. 113-126.

Data and results

AcidsConcentration of acid after dilutionExperimental pHTheoretical pH% error HCI 12*10-2 M2.121.6920.28%
HCI 28*10-4 M2.643.0917.04%
HCI 33.2*10-5 M3.384.4924.72%
HCI 41.3*10-6 M5.855.880.51%

BasesConcentration of base after dilutionExperimental pHTheoretical pH% error NaOH 12*10-2 M11.4212.317.15%
NaOH 28*10-4 M9.6410.9111.55%
NaOH 33.2*10-5 M8.689.508.63%
NaOH 41.28*10-6 M7.988.101.48%

Combined Concentration of acid and base after combinationExperimental pHTheoretical pH% error 12*10-2 M6.9171.28%
28*10-4 M6.04713.71%
33.2*10-5 M6.7274%
41.3*10-6 M6.3279.71%

Mass of Salt: 0.186

Calculations

1.Concentration of Dilution: M1V1 = M2V2
(1.0mL)(0.5M) = (25mL)(X)
X = 0.02

2.pH Calculation: -log(H+)
-log(2 *10-2 M) = 1.69

3.pH from pOH: 14-pH = pOH
14 – 2= 10

4.Percent Error: Actual Value (2.12) – Theoretical Value(1.69) * 100 = 20.28% Theoretical Value (1.69)

5.Percent Yield: Experimental Yield (g) *100
Theoretical Yield (g)

Conclusion

After putting together data and analyzing the reactions closely, one can see which metals create the heaviest flow of electrons, and which don’t. Magnesium and iron seem tend to have the highest flow of electrons...