Essay on Acid Base Titration Lab

Submitted By kahoff
Words: 1497
Pages: 6
Open Document
LAB REPORT

Kim Hoff
Damien Guilband
Noah Jabusch
03/09/15 ­ 3/10/2015
Acid­Base Titration Lab

INTRODUCTION
:
The purpose of this acid­base titration lab was to determine the molar concentration of two acid solutions by performing titrations with a strong base, NaOH, of known concentration. The pH of the solution was monitored and graphed with a pH meter over the course of each titration. The pH graph was used to find the equivalence points of both reactions, allowing the calculation of the concentrations of both acids. The K value for acetic acid was also calculated, using the a
Henderson­Hasselbach equation and the halfway point that was identified on the pH graph.

CHEMICAL EQUATIONS: HCl (aq) + NaOH(aq)
→
NaCl(aq) + H
O (l)
2
­
­
OH (aq) + HC
H
O (aq) → C
H
O (aq) + H
O (l)
2
3
2
2
3
2
2

MATHEMATICAL FORMULAS:
M = concentration (moles/liter)

M =n÷V

n = amount of solute (moles)
V = volume of solution (liters)

|
Percent error = ||accepted value − experimental value accepted value
| × 100

pH = negative logarithm of hydrogen concentration
­
pH = pK + log([A
]
/
[HA])
a

pK = ­log(K
)
a a K
= equilibrium constant of a weak acid a ­
[HA] and [A
] = concentrations of a weak acid and its conjugate base, respectively.

HAZARDS:
Chemical Name

Formula Properties

Hydrochloric acid

HCl

Sodium Hydroxide NaOH
Acetic acid

Health Hazards

colorless, strong odor, acidic pH Skin/Eye burns or irritation colorless, odorless, basic pH

HC
H
O
2
3
2 colorless with vinegar odor

Skin/Eye burns or irritation
Skin/Eye irritant

PRE­LAB QUESTIONS
−

1mol KHP × 1mol HP × 1mol NaOH ×
1
1)
0.685g
KHP × 204.22 g KHP

0.181
M NaOH
1mol KHP
.0185L NaOH =
1mol HP −
1mmol CH 3NH 2
1mL CH 3NH 2
2) 15 mL HCl × .2mmol HCl
× .175mmol CH =
17.1 mL CH
3NH

2
1mL HCl ×
1mmol HCl
3NH 2

QUALITATIVE DATA:
The solutions used in this lab were all originally colorless. As the NaOH solution was added to the acetic and hydrochloric acids, no changes in either solution were observed. RAW QUANTITATIVE DATA:
Hydrochloric Acid titration Volume of
NaOH (mL) 1.95 9.11 10.18 11.18 12.00 12.21 12.34 12.50 12.60 12.67 12.79 12.79 12.82 pH 2.32 2.75 2.91 3.10 3.40 3.51 3.67 3.85 4.06 4.23 4.46 4.80 5.60 dpH/dV 0.06 0.08 0.15 0.26 0.38 0.71 1.15 1.53 2.08 2.51 5.48 28.11 14.94
2
2 d pH/dV
0.005 0.01 0.07 0.15 0.45 1.83 2.81 3.69 7.07 42.47 161.7 230.3 10.45 12.90 12.92 12.96 13.00 13.05 13.29 13.40 13.61 13.80 14.08 14.62 16.22 18.43
6.26 6.83 8.95 9.67 10.08 10.72 10.97 11.20 11.32 11.47 11.67 11.96 12.15
16.34 37.39 32.21 11.90 3.94 2.54 1.56 0.90 0.57 0.38 0.21 0.12 0.08
157.7 170.7 ­240.0 ­240.8 ­44.73 ­10.53 ­4.90 ­2.56 ­1.11 ­0.39 ­0.12 ­0.04 ­0.02 Acetic Acid titration
Volume of
NaOH (mL) 1.10 1.93 3.29 5.12 6.10 7.35 10.38 11.04 11.90 12.10 pH 3.73 4.15 4.56 4.87 5.01 5.21 5.74 5.89
6.18 6.31 dpH/dV 0.47 0.35 0.24 0.17 0.15 0.17 0.19 0.27
0.39 0.59
2
2 d pH/dV ­0.13 ­0.09 ­0.06 ­0.03 ­0.003 0.01 0.03 0.12
0.28 0.51 12.49 12.70 12.90 13.01 13.23 13.40 13.60
6.56 6.71 6.97 7.35 8.22 9.48 10.11
0.70 1.06 2.14 3.84 5.12 4.95 3.80
1.09 3.52 7.99 7.89 2.68 ­2.42 ­5.04

CALCULATED QUANTITATIVE DATA:

With hydrochloric acid

With acetic acid

Moles of NaOH used

0.0011

.0012

Concentration (mol/L)

0.11

0.12

Percent error (concentration)

10.0%

20.0%

K a –

­6
9.8 × 10

Percent error (K
)
a

–

45.7%

SAMPLE CALCULATIONS:
Moles of NaOH
M = n÷V
0.10 M = n ÷ .01099 L, n = 0.0011 mol Concentration of acid
M = n ÷ V , 1 mol NaOH:1 mol HCl
.0011 mol NaOH: .0011 mol HCl
M = .0011 mol ÷ .010L = .11M

Percent error
|
Percent error = ||accepted value − experimental
Show More

Related Documents: Essay on Acid Base Titration Lab

Summary: Ionization Constant Of A Weak Acid

of the lab that was performed within Chemistry II 153L is titled “Ionization Constant of a Weak Acid, Ka” This lab is very important because it incorporates a great amount of theories that we have learned throughout our Chemistry course. By the word ‘theory’ this can be defined as a well-established explanation for scientific data. Theories typically cannot be proven, but they can be established if several different scientific investigators test them. These theories are named, Arrhenius acids and bases…

Words 1715 - Pages 7

Essay on Week 5 iLab Report

Week #5 UNKNOWN ACID AND BASE TITRATION Introduction The purpose of this lab is to determine the concentration of a hydrochloric acid solution using acid-base titration. When the base was added to the acid, the indicator in the acid turned the solution pink when the end point of titration was reached. Procedure Part I: Measuring pH Step 1: Measure pH of 0.1 M hydrochloric acid 1) Select Equipment from the toolbar 2) Select a 100 mL beaker 3) Add 50 mL of 0.1 M hydrochloric acid to the beaker…

Words 814 - Pages 4

Sodium Hydroxide and Ph Essay

Chapter 14/15 Review 1. What is an acid? Give 3 examples… Acid: 1) 2) 3) 2. Provide 4 properties of acids 1) 2) 3) 4) 3. What is a base? Give 3 examples… 1) 2) 3) 4. Is CH3COOH an acid or a base? Check your notes! 5. What is a strong acid/base? And how is it different from a weak acid/base? Give an example of each… Strong Acid/base: Weak Acid/base: 6. What two products are always made when you add an acid and base together in solution? 7. H+…

Words 462 - Pages 2

acid base expiriment Essay

Acid-Base Titration A titration is a process used to determine the volume of a solution needed to react with a given amount of another substance. In this experiment we titrated a hydrochloric acid solution, with a basic sodium hydroxide solution. The concentration of the NaOH solution was given and we had to determine the unknown concentration of HCL. The hydrogen ions from the HCL react with hydroxide ions from the NaOH in a one-to-one ratio to produce water in the overall reaction. When…

Words 389 - Pages 2

Earth: Ph and Equivalence Point Essays

Strong Acid-Strong Base Titration Renee Y. Becker Valencia Community College Introduction A titration is a procedure in which one standardized substance (titrant) is carefully added to another (analyte) until complete reaction has occurred. By accurately measuring the volume of each solution required to reach the equivalence point (equal molar amounts of acid and base) of the reaction the concentration of the unknown solution can be determined. In this strong acid-strong base titration…

Words 1340 - Pages 6

Thymol Blue And Ethanoate Lab Report

Lab Proposal: Determining the Effectiveness of Thymol Blue and Ethyl Bis Ethanoate compared to that of Phenolphthalein in Determining the Molarity of NaOH Background As described in our Atkins textbook, an acid-base indicator “changes color with pH because it is a weak acid that has one color in its acid form and another color in its conjugate base” (538). The equation of the proton-transfer that the indicator undergoes is as follows: 〖HIn〗_((aq) )+〖H_2 O〗_((l) )⇋〖H_3 O^+〗_((aq) )+〖In^-〗_((aq)…

Words 1037 - Pages 5

Moolar Mass Of Citric Acid

Citric Acid Purpose: 1) To observe the molar mass of citric acid 2) To familiarize yourself with titration techniques Procedure: 1) Sanitize the burets with the soap solution provided in lab and rinse with water. After this rinse, also rinse twice with a little bit of deionized water making sure that the water flows freely through the open stopcorks. Fixture the burets upside down so the stopcorks can drain. 2) Sanitize the Erlenmeyer flasks with the soap solution provided in lab and rinse…

Words 599 - Pages 3

Essay about Titration: Acid and Unknown Solid Acid

Potentiometric Titrations of a Weak Acid with a Strong Base Objective In our next lab, we are going to use our titration that involves our unknown solid acid and our base, which is NaOH. We will titrate our unknown solid acid with NaOH and each 0.5 increments and measure their pH by using the Venier device. Then, using our data, we will determine our equivalence point. From Exploring Chemical Analysis, an equivalence point is the titration of the quantity sufficient for stoichiometirc reaction…

Words 693 - Pages 3

Detection of Ions in Solutions Using Acid/Base Chemistry: A Quality Control Test Essay

Solutions Using Acid/Base Chemistry: A Quality Control Test Objective: This lab focuses on the detection of ions using titration as an analysis tool. You will standardize NaOH and HCl solutions so that you know the exact concentration and then prepare samples of common household items in order to determine the amount of calcium in Tang®, Mg(OH)2 in Milk of Magnesia, etc. You will learn to prepare samples of a specified concentration, learn about acids and bases through the use of titrations and learn…

Words 2736 - Pages 11

Titration and Naoh Essay

Titration of Acids and Bases Purpose: To determine the amount of acid in an unknown and become familiar with the techniques of titration. Hypothesis: If one uses a neutralization reaction for a solution, one can determine the concentration of a solution. Materials: • 50mL burette • 600mL beaker • 500mL Erlenmeyer flask • 250mL Erlenmeyer flasks(3) • Weighing bottle • Ring stand and ring • Balance • Bunsen burner and hose • 1 pint bottle with rubber…

Words 1709 - Pages 7