Vapor Pressure of Liquids & Solutions
VAPOR PRESSURE OF LIQUIDS & SOLUTIONS
Adapted from "Chemistry with Computers" Vernier Software, Portland OR, 1997
OBJECTIVES For you, the student, to write.
SAFETY Wear safety goggles and lab apron at
A titration curve is a plot of pH versus volume of titrant. The titrant, ~0.1 M NaOH, will
be slowly dripped from a buret (solvent reservoir) into the acid solution which contains a
computer- interfaced pH electrode. Volume will be recorded by arranging a
A weak acid (HA) dissociates in water according to the equation: (1) HA (aq) + H2O (l)
H3O+ (aq) + A (aq) Ka
= [H3O+] [A] / [HA] The acid dissociation constant is algebraically rearranged to the
(2) [H3O+] = Ka [HA] / [A]
Taking the negative lo
Address the following:
a. What are some applications of the titration/fluorescence measurement of magnesium?
b. Describe the basic concepts being applied to make the measurements. Include:
1. Complexation of magnesium with Calmagite and EDTA.
1. Include absorbance and fluorescence spectra.
2. Include tables containing key pieces of the raw data (absorbance at volumes as the
titration proceeds, fluorescence of unknown and the standards provided). 3. Plot of
absorbance vs. vol
In an acidbase titration, the concentration of an analyte (acid or base) is quantitatively
determined by the addition of a known volume of titrant (base or acid, respectively) in
the presence of a good indicator. What is an indicator and what
References. Always required. Lab manual website must be cited.
Statistical Analysis. Required.
All statistical analysis must be done in excel and the excel file must be uploaded into
An endpoint is the titrant volume and solution pH at which the indicator changes color.
Endpoints are a property of the indicator being used, not a function of the titrant or
analyte. An indicator is a weak acid that when deprotonated (forming its conjuga
Bromothymol blue will also be used to show how pH can control speciation. Five buffer
solutions ranging from pH 1 to 13 will be created. Because bromothymol blue is a weak
acid that changes color when deprotonated, the amount of each species (HIn or In) i
The equivalence point is the inflection point of a titration curve. As a sigmoidal shaped
curve, the inflection point is where the curvature changes sign (or direction) on a titration
curve. Note: (1) The pH of the inflection point can be used to pick an
Erythropoietin The human growth hormone erythropoietin (EPO) is secreted primarily by the kidneys. It binds to receptors located on the surface of precursor cells in bone marrow that develop into red blood cells. In doing so, it protects the precursor cel
RDG: Aerosols and Ozone
AEROSOLS AND OZONE
Organic Aerosols in the Atmosphere Airborne particles are important for visibility, human health, climate, and atmospheric reactions. Atmospheric particles contain a significant fraction of orga
LIQUID CHROMATOGRAPHY: Separating Mixtures Based on Polarity Differences
OBJECTIVES A mixture of three compounds will be separated using a column of silica gel and solvents of varying polarity. After solvent evaporat
SELF-ASSEMBLED MONOLAYERS (SAMs)
Theresa M. McIntire, Sergey A. Nizkordov, and Kimberly Edwards Department of Chemistry, University of California, Irvine, Irvine, CA 92697-2025
OBJECTIVE The goal of this laboratory experiment is to f
A gradual change in pH occurs as the base is initially added to the acidic solution. For a
weak acid, such as acetic acid, this section of the titration curve is referred to as the
buffering region. As base is added it reacts with the acid and forms a buf