Proyecto PID11011

1. Memoria de seguimiento.
Proyecto PID 11011 “Docencia en lengua inglesa de asignaturas de Química
Analítica del Grado en Química de la Universidad de Huelva”
XVI Convocatoria de proyectos de innovación e investigación para la mejora de en
docencia universitaria.
Coordinador: Daniel Alejandro Sánchez-Rodas Navarro
A lo largo del curso 2011/2012 se ha ido elaborando el material en inglés de las
actividades académicas dirigidas de la asignatura Química Analítica Instrumental de 2º
curso del Grado en Química. El material comprende controles tipo test de respuesta
única a elegir entre varias opciones, así como colecciones de problemas en inglés. El
material generado se adjunta en el Anexo I.
El material está dirigido inicialmente a alumnos Erasmus que no dominen el español,
pero durante el curso 2011/2012, no se ha tenido alumnos de este tipo en la asignatura.
En el curso actual 2012/2013, sí se tiene un alumno de Turquía que seguirá la
metodología de Actividades Académicas en inglés. Igualmente se ha ofertado a los
alumnos españoles la posibilidad de realizar las Actividades Académicas en inglés a lo
largo del presente curso.
Para fomentar la participación del alumnado, se aumentará un 10-20 % la calificación
de las Actividades, reflejándose dicho aumento en los criterios de evaluación de la guía
docente de la asignatura. En el primer contacto con los alumnos, en torno a un 30%
mostraron su intención de realizar dichas actividades en inglés. A final de curso se
realizará una encuesta respecto a la experiencia y se evaluarán los resultados para
introducir modificaciones y/o mejoras.

2. Anexo I. Material en inglés.
QUÍMICA ANALÍTICA INSTRUMENTAL
Grado en Química
ACTIVIDAD ACADÉMICA DIRIGIDA I.
TEST.
Chapters 1 and 2. Introduction to Instrumental Analysis. Introduction to Optical Techniques.
(mark only one answer for each of the following questions)
1. Which of the following statements on detection limit is false?
a) It can be calculated after measuring several times the signal of a blank
b) It can be defined as the signal of a blank plus three times its standard deviation
c) It can be calculated using the calibration graph
d) The concentration at the limit of detection is lower than the concentration at the limit of
quantification
e) The concentration at the limit of detection is higher than the concentration al the limit of
quantification
2. Which of the following statements about calibration is false?
a) The usable calibration range is from the limit of quantification to the limit of linearity
b) The usable calibration range indicates that there is a linear relationship between the signal
of the instrument and concentration
c) The portion of the calibration graph between the limit of detection and the limit of
quantification can never be employed
d) The portion of the calibration graph between the limit of detection and the limits of
quantification should not be employed
e) You can never measure below the limit of detection
3. Which of the following statements on the Jonhson noise is false?
a) It orginates on the thermical movement of electrons
b) It is produced randomly
c) It decreases as the eleletrical resistence of the instrument circuits also decreases
d) It decreases as the temperature of the components of the instruments decreases
e) It decreases as the physical size of the electrical resistence decreases
4. Mark the correct order from the longest to shortest wavelength of the different zones of the
electromagnetic spectrum:
a) X rays, ultraviolet, visible, microwaves
b) microwaves, ultraviolet, visible, infrared
c) X rays, ultraviolet, visible, infrared
d) microwaves, infrared, visible, ultraviolet
e) infrared, visible, X rays, ultraviolet
5. Mark the portion of the electromagnetic spectrum responsable for vibrational changes in the
molecules:

3. a) X rays
b) ultraviolet
c) visible
d) infrared
e) microwaves
6. Which of the following processes corresponds to the emission of energy?
a) X → hv + X*
b) X + hv → X*
c) X* → hv + X
d) X* → hv + heat
e) none of them
7. Which of the following statements is the best definiton for fluorescence?
a) Emission of radiation without changing the spin of the electron
b) Absorption and later emission of radiation without changing the spin of the electron
c) Absorption of radiation without changing the spin of the electron
d) Absorption and later emission of radiation with change of the spin of the electron
e) Absorption of radiation of ultraviolet radiation
8. Which of the following electronic transitions takes place at the shortest wavelength?
a) 3s → 3p
b) 3s → 4p
c) 3p → 3s
d) 4p → 3s
e) all of them emit at the same wavelength
9. Hollow Cathode Lamps are used for...:
a) Atomic Emission
b) Atomic Absorption
c) Molecular Fluorescence
d) Phosphorescence
e) Bioluminiscence
10. Mark the typical order of components of the configuration for a molecular aborption
spectrophotometer:
a) radiation source, cuvette, detector, λ selector
b) radiation source, λ selector, cuvette, detector
c) λ selector, cuvette, detector
d) cuvette, λ selector, detector
e) radiation source, λ selector, detector

4. QUÍMICA ANALÍTICA INSTRUMENTAL
Grado en Química
ACTIVIDAD ACADÉMICA DIRIGIDA II.
Problems
Chapter 3. UV-Vis Absorption Spectroscopy
1. A solution of a molecular compound was prepared dissolving 36.3 mg into a volumen of
100 mL. This solution had a transmittance value of 31.4% measured in a 2 cm cuvette at a
wavelength of λ 260 nm. Data: ε 2300 L cm-1 — mol-1
a) Calculate the Molecular Weight of the molecular compound
b) Knowing that the ε value drops to its half when measured at 340 nm, which should
be the molar concentration of the compound, so the absorbance may remain the
same using also a 1 cm cuvette?
c) Which molar concentration should the solution have, so the T may be double using
a 2 cm cuvette, measuring at 260 nm?
2. Absorbance was measured at 330 nm for a solution of 100 mL of 50 ppm of nitrate. A
0.440 U.A. value was obtained using a 1 cm cuvette.
Data: At. Weight for N 14, At. Weight for O 16, At. Weight for C 12
a) Calculate the molar absortivity value at that wavelength
b) Which would be the new value of absorbance, if this solution is mixed with 15
mL of another solution of 250 ppm of nitrate?
3. The molar absortivities for the Zn, Ni and Cd complexes with a ligand L are the
following, measured at three wavelenghts:
Complex λ I (485 nm) λ II (553 nm) λ III (637 nm)
Ni-L 1.6x102 1.2x103 4.7x102
Zn-L 0 0 6.3x103
Cd-L 2,6x103 4.2x103 0
The absorbance values were 0.306 U.A. at 485 nm, 0.619 U.A. at 553 nm and 0.945
U.A. at 637 nm.
Calculate the concentrations of the Zn, Ni and Cd complexes.
4. The photometric titration of a mixture of Ni and Ca was undertaken using a ligand L as
titrant. The following data of molar absortivities were obtained at two wavelengths:
λ I (440 nm) λ II( 680 nm)
Ni 1.2x103 0
Ni-L 0 0
L 0 1.2x103
Cd 0 1.2x103
Cd-L 1.2x103 0
Data: K Ni-L 5.8x103, KCd-L 4.5x105
a) Draw the titration graph at 440 nm
b) Draw the titration graph at 680 nm

5. QUÍMICA ANALÍTICA INSTRUMENTAL
Grado en Química
ACTIVIDAD ACADÉMICA DIRIGIDA III.
TEST.
Chapters 3 and 4. UV-vis Molecular and Emission Spectroscopy
(mark only one answer for each of the following questions)
1. Mark the sentence about absorbance and transmittance that is right:
a) The higher the capacity that the analyte has to absorb radiation, the higher is the value of
transmittance
f) Transmittance is calculated dividing the transmitted power by the incident power
g) Absorbance and transmittance are directly proportional
h) Absorbance is calculated as the logarithm of transmittance
i) Absorbance values are within 0 and 100%
2. Mark the sentence about the Lambert-Beer Law that is false:
f) For a certain analyte, its ε depends on the wavelength used for measurement
g) The Lambert-Beer Law is fulfilled at low analyte concentration, < 0.01 M
h) The more monochromatic the radiation is, the better the Lamber-Beer Law is fulfilled
i) If the radiation is polychromatic, and the several ε values are very similar, the Lambert-Beer
Law is fulfilled
j) If the radiation is polychromatic, and the several ε values are very different, the Lambert-
Beer Law is fulfilled
3. Mark which of the following compounds cannot be measured by UV-vis Molecular Absorption
Spectroscopy:
a) benzene
b) CH2=CH-CH=CH2
c) C2H6
f) (CH3)3N
g) phenol
4. An hypsochromic shift in Molecular Absorption Spectroscopy….
a) ...involves an electronic transition from n to σ*
b) ...is a shift to longer wavelengths
c) ...means that the ε increases
d) ...involves an electronic transition from π* to n
e) ...is due to a decrease of the energy of the n level
5. Mark the sentence about the determination of phosphate that is false:
f) It is based on the formation of a molibdate-phosphate complex
g) The absorbance is measured in the visible range
h) A reductant is used to reduce some Mo(VI) to Mo(V), (Molibden blue method)
i) Fe and silicates are interferences for this method
j) Turbidity is measured after adding sulphate

6. 6. Mark the sentence about Luminiscence that is false:
a) In photoluminiscense, excitation occurs due to absorption of photon energy
b) In Chemiluminiscence, excitation occurs due to a chemical reaction
c) In phosphorescence, the emission process is from an excited state triplet to a ground state
singlet
d) Vibrational relaxation is a slow process
e) Internal Conversion means a change from a excited single state of high energy to another
single excited state of lower energy
7. Which of the following processes corresponds to External Conversion?
a) loss of energy from a higher vibrational energy level to a lower vibrational energy level
b) a change from a ground state singlet to an excited state singlet
c) a change from a excited single state of higher energy to another single excited state of lower
energy
d) loss of energy of an excited state to a ground state without the emission of radiation
e) a change from a excited state singlet to a excited state triplet
8. Which of the following compounds could be more phosphorescent?
f) benzene
g) fluorobenzene
h) chlorobenzene
i) bromobenzene
j) All of them could present the same phosphorescence
9. Which is the typical configuration of a spectrofluorimeter?
a) radiation source-monochromator-cuvette-detector
b) radiation source-cuvette-monochromator-detector
c) radiation source-monochromator-cuvette-monochromator-detector
d) radiation source-filter-cuvette-filter-detector
e) none of them
10. Which of the following compounds is not analyzed by Chemiluminiscence?
a) NO
b) NO2
c) O3
d) N2
e) SO2

7. QUÍMICA ANALÍTICA INSTRUMENTAL
Grado en Química
ACTIVIDAD ACADÉMICA DIRIGIDA IV.
TEST.
Chapter 5. Infrared (IR) Spectroscopy
(mark only one answer for each of the following questions)
1. The zone of Infrared most used for analysis corresponds to:
a) The near-infrared
j) Far-infrared
k) 0.78-2.5 m
l) 2.5-15 m
m) 50-100 m
2. Mid-infrared is used for the analysis of:
k) solids
l) solids and liquids
m) solids and gases
n) liquids and gases
o) solids, liquids and gases
3. Which of the following is the radiation source used in far-infrared analysis?
a) Hg vapour
b) Nerst emissor
c) Globar emissor
h) Wolframiun emissor
i) CO2 laser
4. A piroelectric detector…
a) ...has two metal joints (Sb y Bi)
b) ...contains a dielectric material (non-conductive) capable of electric polarization
c) ...contains a semiconductor film
d) ...generates an electric current due to photons
e) ...it is built using CdTe o HgTe
5. Mark which of the following sentences about the Michelson Interferometer is false:
k) It uses two mirrows, one fixed and the other mobile
l) The mobile mirrow moves at a constant speed
m) It generates a signal called interferogram
n) It converts a signal of low frecuency into another of high frecuency
o) It uses Fourier Transform to convert a function from a time domain to a frecuency domain

8. 6. IR photometers without filters are used for the analysis of:
a) most organic compounds
b) atmosheric gaseouos organic compounds
c) inorganic compounds
d) organometallic compounds
e) none of the above
7. Which of the following sentences about the medium-IR spectra of 3-
methylhexane and 3,3-dimethylhexane is correct?
a) both spectra will be identical
b) the group region of the sepctrum will be similar for both compounds
c) the group region of the spectrum will be different for both compounds
d) the fingerprint region of the spectrum will be identical for both
compounds
e) it is not possible to obtain the medium-IR spectra of those compounds
8. Which of the following is not a disadvantage in quantitave IR determinations?
k) The Lamber-Beer Law is frequently not fulfilled
l) Spectra are usually very complex
m) The analytes have a great calorific capacity
n) The use of narrow cuvettes causes uncertainty in the determinations
o) The analytical errors are bigger than in UV-visible methods
9. Which of the following sentences about Inner Reflexion IR is false?
a) It is used for samples which are difficult to handle
b) It is based on the principle of Attenuated Total Reflectance
c) It used a transperent, cristaline material with a high refraction index
d) The beam of radiation crosses from a high density medium to a low
density medium
e) The beam of radiation penetrates into the high density medium
10. Mark which of the following sentences about NIR is false
a) It is applied to solids converted into fine particles
b) It uses near-IR radiation
c) It uses BaSO4 as difuse reflectant material
d) Calibration is easy
e) Calibration is compared to the results obtained with an official method
of analysis