niryuu/sni-each-converted huggingface dataset:
Question: Which of the following symptoms is characteristic of inattention in Attention Deficit Hyperactivity Disorder (ADHD)? : 
 Options:  <1> They usually have difficulty organizing tasks and activities. <2> They usually answer before ending the question. <3> They usually have difficulty playing quietly. <4> They are usually stirred in their seat. <5> They usually interfere in the activities of others.
Output: 1
Question: According to the phenomenon of social facilitation when a person develops a task poorly learned in the presence of others, the execution of said task: 
 Options:  <1> It improves slightly. <2> It improves substantively. <3> It does not change. <4> Gets worse. <5> It is not predictable.
Output: 4
Question: The hormone that facilitates the reabsorption of water by the kidneys, whose absence causes loss of large amounts of water in the urine, is called: 
 Options:  <1> Oxytocin <2> Vasopressin <3> Dopamine <4> Cholecystokinin <5> Glutamate.
Output: 2
Question: The complexes of cobalt (III): 
 Options:  <1> They are all neutral or anionic. <2> They form the basis of our knowledge about the properties and reaction mechanisms of octahedral complexes. <3> They are usually flat-squares. <4> They present very fast substitution kinetics. <5> Almost all are prepared by replacing some ligands with others.
Output: 2
Question: A homogeneous reaction between ideal gases that has reached chemical equilibrium can evolve (ie, move towards the formation of more reactants or products) in the following way if this equilibrium is altered: 
 Options:  <1> If the temperature is increased at constant pressure, it will go to where more moles will be produced. <2> If the pressure is increased to constant temperature it will go to where the volume is higher. <3> If an inert gas is added it will go to where this gas is consumed. <4> If a gas that participates in the reaction is added, it will go to where more gas is produced. <5> If the temperature is decreased, it will go to where the reaction is exothermic.
Output: 5
Question: When the manganese is oxidized in the air at 1000 ºC it is completely transformed into Mn3O4. This is because: 
 Options:  <1> Mn3O4 is the most volatile of all manganese oxides. <2> Mn3O4 can no longer react with oxygen. <3> There are no manganese oxides with a higher oxidation state. <4> Mn3O4 is the most stable of all manganese oxides. <5> Mn3O4 forms a protective layer that stops oxidation of the metal.
Output: 4
Question: Comparing the redox behavior of the silver and sodium systems: 
 Options:  <1> Na + is a good oxidant, because its system has a high reduction potential. <2> Ag is an excellent oxidant, so it does not rust in the air. <3> Ag + is a good oxidant, and therefore easily reducible to metal. <4> The two metals dissolve in acid medium releasing H2 <5> The two metals dismute spontaneously in water.
Output: 3
Question: Graphite: 
 Options:  <1> It gives intercalation compounds with fluorine. <2> Reacts with sodium to give a covalent compound with C ̶ Na bond. <3> Reacts with sodium to give intercalation compounds that have the same distance between layers that pure graphite had. <4> Reacts with sodium to give intercalation compounds that are better electrical conductors than pure graphite. <5> It gives covalent compounds with bromine with C ̶ Br bond.
Output: 4
Question: By heating in electric furnaces of silica, calcium carbide and coal, calcium silicides are obtained. One of them: 
 Options:  <1> It has the composition CaSi2. <2> It does not react with water. <3> Does not react with sulfuric acid. <4> It is a powerful oxidizing agent. <5> Its reaction with liquid water generates calcium silicate.
Output: 1
Question: The change of internal energy when a mole of solid is formed from gaseous ions at infinite separation, at atmospheric pressure and at 0 K is called energy: 
 Options:  <1> Deformation. <2> Of sublimation. <3> Reticular <4> Of condensation. <5> Of liquefaction.
Output: 3
Question: The Nernst equation: 
 Options:  <1> It is true both for reversible and highly irreversible galvanic cells. <2> It allows to calculate the electromotive force of a galvanic cell with only knowing the Gibbs energy standard of the chemical reaction of the cell. <3> It depends solely on the activities of the species that participate in the chemical reaction of the cell. <4> It relates the electromotive force of the cell with the activities of the species that participate in the chemical reaction of the cell and with the standard potential of the reaction. <5> It is independent of the number of electrons transferred in the electrochemical reaction of the cell
Output: 4
Question: A mixture of iron (III) chloride and potassium hexacyanoferrate (III) (potassium ferricyanide) is used to detect extremely small amounts of hydrogen peroxide in the water. The presence of H2O2 causes, after a short time, an intense dark blue color. This is because hydrogen peroxide: 
 Options:  <1> It reduces hexacyanoferrate (III) to hexacyanoferrate (II). <2> Oxide to hexacyanoferrate (III). <3> Oxide to iron (III) chloride. <4> Peroxo-cyano form complexes of Fe (III). <5> Oxidize cyanocomplexes to complex cyanate.
Output: 1
Question: For the industrial production of tin, the ore is split: 
 Options:  <1> Cinnabar. <2> Blende. <3> Wurtzita <4> Casiterita. <5> Pyrite.
Output: 4
Question: The mechanism of a homogeneous chemical reaction: 
 Options:  <1> It may include reaction intermediates that are not any of the reactants or any of the products. <2> It is completely defined by the chemical reaction as long as it reflects the correct stoichiometry of the reaction. <3> It is only defined for complex reactions in which the reactants go through many stages before becoming products. <4> It is totally independent of the law of reaction speed. <5> It does not depend on the temperature and is unique for the reaction between certain reagents.
Output: 1
Question: The color centers or F centers are produced: 
 Options:  <1> Exclusively in crystals that contain fluorine. <2> By heating a crystal in the vapor of an alkali metal. <3> By cooling a crystal in the vapor of an alkali metal. <4> By heating a crystal in the presence of fluorine. <5> By cooling a crystal in the presence of fluorine.
Output: 2
Question: By cooling rapidly to room temperature and tempering an ordinary (low carbon) steel in water, the structure known as: 
 Options:  <1> Perlite <2> Spheroidite <3> Bainita <4> Ferrita. <5> Martensita
Output: 5
Question: The ceramic materials are: 
 Options:  <1> Hard and fragile. <2> Tenacious and ductile. <3> Soft and malleable. <4> Ductile and malleable. <5> Soft and fragile
Output: 1
Question: The treatment consisting of keeping a material at an elevated temperature for a period of time and then cooling it slowly is called: 
 Options:  <1> Normalized <2> Tempered. <3> Annealing. <4> Restored <5> Sintered
Output: 3
Question: Calcium hydroxide: 
 Options:  <1> It is prepared by adding water to calcium oxide. <2> It is a compound of intense red color. <3> It crystallizes when heated. <4> In solution it remains unchanged in air for months. <5> It is used to paint after neutralizing with HCl.
Output: 1
Question: The Arrhenius equation: 
 Options:  <1> It relates the speed of a chemical reaction with the so-called constant velocity and with the concentrations of the reactants raised to their stoichiometric coefficients. <2> It relates the constant of speed of a chemical reaction with the energy of activation of said reaction, so that if the energy, of activation is high the reaction is fast. <3> It is only fulfilled for unimolecular reactions. <4> It relates the speed constant to the temperature through the activation energy and the pre-exponential factor. <5> It allows to obtain the activation energy of an elementary reaction by only representing the decimal logarithm of the temperature versus the inverse of the reaction time.
Output: 4
Question: If metallic copper is added to a solution of iron (III) chloride, it produces: 
 Options:  <1> A precipitate of copper (II) chloride. <2> A solution of copper (II) chloride and iron (II) chloride. <3> A precipitate of iron (II) chloride. <4> A precipitate of metallic iron. <5> A solution of copper (I) chloride and iron (II) chloride.
Output: 2
Question: The matrices of the composite materials can be: 
 Options:  <1> Polymeric <2> Polymeric or metallic, but not ceramic. <3> Polymeric or ceramic, but not metallic. <4> Metallic or ceramic, but not polymeric. <5> Polymeric or metallic or ceramic.
Output: 5
Question: Calcium fluoride is a white solid that is found as such in nature (fluorspar or fluorite, which can occur in many colors) and is used as an important source of fluoride. Among its physical and chemical properties include: 
 Options:  <1> Its solubility in water, which differentiates it from the other group 2 fluorides. <2> Its resistance to concentrated sulfuric acid. <3> Its hydrolysis in water, which transforms it into CaO and HF. <4> Its relatively low melting point for a mineral. <5> Its favorable, although slow, oxidation to the air.
Output: 4
Question: With respect to the distribution coefficient of a solute between two partially miscible liquids: 
 Options:  <1> Because it is a quotient between solute concentrations in the two phases, it is independent of temperature. <2> It does not depend on the total amount of solute in both parts. <3> It is useful to determine the molar mass of the solute. <4> If one phase is water and the other an organic solvent, it is usually used in medical and environmental chemistry to know the distribution of drugs and contaminants between these two types of media. <5> It only has physical significance when the liquid phases are in contact through a semipermeable membrane.
Output: 4
Question: Osmium oxide (VIII), OsO4: 
 Options:  <1> It is a compound in a state of oxidation very common among transition metals. <2> It is the only binary compound of osmium with oxygen. <3> It has the structure of rhenium trioxide. <4> It is inert compared to alkaline hydroxides. <5> It is used as an oxidant in organic chemistry.
Output: 5
Question: In relation to the colligative properties of a solution it can be said that: 
 Options:  <1> They have their origin in the decrease of the chemical potential of the solvent by the fact of adding a solute. <2> The decrease in the vapor pressure of the solvent to which a non-volatile solute is added is directly proportional to the mole fraction of the solvent. <3> The addition of a solute to a solvent causes the range of temperatures in which the solution is maintained in the liquid state to be lower than that corresponding to the pure solvent. <4> The molal constant of descent of the freezing point depends on the nature of the dissolved solute. <5> Cryoscopic descent is a technique applicable to the determination of the molar mass of the solvent.
Output: 1
Question: The SO2 molecule is: 
 Options:  <1> Linear, with the S atom in the center. <2> Linear, with one of the atoms of O in the center. <3> Angular, with the S atom in the center and with an angle close to 120º (equilateral triangle) and a free pair of electrons. <4> Angular, with one of the atoms of O in the center and with an angle of approximately 120º (equilateral triangle) and a pair of free electrons. <5> Angular, with the S atom in the center and with an angle close to 109º (tetrahedron) and two pairs of free electrons.
Output: 3
Question: Gallium is the element that is under the aluminum in group 13 of the periodic table. Thus: 
 Options:  <1> It burns in oxygen giving Ga2O. <2> It is stable to air due to a protective oxide layer. <3> It dissolves very quickly in nitric acid. <4> It is not soluble in basic water with hydrogen evolution. <5> It has a melting point a little higher than aluminum.
Output: 2
Question: An isolated carbon atom is: 
 Options:  <1> Diamagnetic <2> Ferromagnetic. <3> Paramagnetic, with an unpaired electron. <4> Paramagnetic, with two unpaired electrons. <5> Paramagnetic, with three unpaired electrons.
Output: 4
Question: If we try to dissolve ammonia in water we observe that: 
 Options:  <1> It is completely soluble. <2> It is not very soluble. <3> It should be poorly soluble, but the solubility increases markedly by acid-base reaction between them, resulting in an acid solution. <4> It should be poorly soluble, but the solubility increases markedly by redox reaction between them, releasing hydrogen. <5> It is very soluble, favored by the formation of hydrogen bonds between the two compounds.
Output: 5
Question: Among the partial reactions that lead to sodium carbonate by the Solvay Process, are: 
 Options:  <1> The reaction between calcium carbonate and sodium chloride. <2> The precipitation of sodium hydrogen carbonate. <3> The thermal decomposition of ammonium chloride. <4> The formation of CaCO3 from CaO and CO2. <5> The reaction of ammonia with calcium oxide.
Output: 2
Question: Van Deemter's velocity equation tries to justify the contributions of the different effects that cause the widening of the chromatographic band, which are basically of four types: 
 Options:  <1> Eddy diffusion, dead volume and resistance to convection in both phases, mobile and stationary. <2> Length of the chromatographic column, longitudinal diffusion in axial and radical direction, and Joule effect. <3> Kinematic viscosity of the mobile phase, mass transport between the mobile phase and the stationary phase, transversal and longitudinal diffusion. <4> Effect of mass transfer in the stationary phase, in the mobile phase, Eddy diffusion and longitudinal molecular diffusion. <5> Molecular diffusion in axial direction, radical atomic diffusion, internal pressure of the column and viscosity of the mobile phase.
Output: 4
Question: Polarography is an analytical technique that refers to: 
 Options:  <1> The absorption of electromagnetic radiation. <2> The emission of electromagnetic radiation. <3> The voltametry with mercury electrode. <4> The use of palladium as a reference electrode. <5> To the potential of asymmetry.
Output: 3
Question: Plasma ICP is more suitable for rapid multielemental analysis than flame atomic absorption methods because: 
 Options:  <1> The linearity interval is not wide, which allows for very sensitive analyzes. <2> The ICP has several possibilities to introduce the sample using different types of nebulizers. <3> They use two photomultiplier tubes, one for the ultraviolet region and the other for the visible one. <4> It has load-coupled silicon solid-state detectors that allow simultaneous monitoring of a large number of lines, reducing analysis time, sample volume and improving detection limits. <5> It is not correct, because with the ICP plasma, multielemental analysis can not be done.
Output: 4
Question: Liquid chromatography in normal phase: 
 Options:  <1> It uses a column with apolar groups that interact with the apolar part of the analytes differentially. <2> It is a mode of operation that employs a polar stationary phase with a low polarity mobile phase. <3> It uses highly polar mobile phases such as alkanes or chloroalkanes. <4> It is a mode of operation that employs a non-polar surface with a mixed aqueous / organic mobile phase. <5> It uses stationary phases with a large number of hydrophobic alkyl ligands.
Output: 2
Question: Every experimental measurement is accompanied by the corresponding experimental error. Experimental errors are classified as systematic and random. On these last ones it is possible to be affirmed that: 
 Options:  <1> They are due to a failure of the experiment or the equipment. <2> They generally cause a positive deviation from the measurement. <3> They are equally likely to be positive or negative. <4> They do not affect the final result because they are random. <5> They affect exclusively the accuracy of the results obtained.
Output: 3
Question: The ionization source known as Inductive Coupling Plasma used in Elemental Mass Spectrometry, is characterized by: 
 Options:  <1> Generate mostly monatomic ions. <2> Fragment the organic molecules in molecular ions that allow their identification. <3> Be a low energy source. <4> Run at high vacuum. <5> Reach detection limits of the order of mg L-1 for most elements.
Output: 1
Question: In gas chromatography, derivatization is very common, with several objectives. One of those discussed below is not among them: 
 Options:  <1> Increase the volatility of non-volatile compounds. <2> Avoid the decomposition of a compound, improving its stability. <3> Reduce the absorption on active surfaces of the walls of the column and the solid support. <4> Fragment the analyte in molecular ions of easier separation. <5> Improve the separation of closely related compounds with a very poor separation.
Output: 4
Question: It is UV visible molecular absorption spectroscopy is called isosbestic point a: 
 Options:  <1> The region of the spectrum where two species have the same radiation emission capacity. <2> The pH at which two absorbing species have the same molecular absorption coefficient. <3> The temperature at which two absorbing species in equilibrium stop emitting radiation. <4> The wavelength at which two absorbing species in equilibrium has the same refractive index. <5> The wavelength at which the molecular absorption coefficients of two absorbent species in equilibrium, interconvertible to each other, are equivalent.
Output: 5
Question: The solubility of copper hydroxide in the presence of a high concentration of ammonia: 
 Options:  <1> Increased by formation of a complex ion of Cu2 + with NH3. <2> It is not affected because there is no common ion effect. <3> Decreases by common ion effect. <4> It decreases upon oxidation of bromide to molecular bromine. <5> It decreases because the hydroxides are more soluble in acidic medium.
Output: 1
Question: In HPLC and under ideal conditions, the chromatographic peaks should have the shape of Gaussian peaks with perfect symmetry, although in reality, the peaks are not perfectly symmetrical and can present fronts and tails. The asymmetry factor: 
 Options:  <1> It is used to measure the relative retention of the two components of a sample so that in perfectly symmetrical compounds it is 0. <2> It is used to measure the degree of symmetry of a peak and is defined at the peak width corresponding to 10% of the peak height. <3> It is a parameter that is calculated by measuring the width at the half-height of the chromatographic peak. <4> It relates to each other two successive chromatographic peaks, so that an asymmetry factor 1 indicates a total resolution of them. <5> It is a parameter related to the symmetry of the peaks, defined at a height equal to 10% of the width thereof.
Output: 2
Question: A calomel electrode: 
 Options:  <1> It is a mercury indicator electrode. <2> It is a reference electrode that contains nitrate ions. <3> It is an indicator electrode for nitrate ions. <4> It is a reference electrode that uses silver and silver chloride. <5> It is a reference electrode that contains a saturated solution of mercury chloride (I).
Output: 5
Question: In atomic fluorescence, the emission of electromagnetic radiation called resonance florescence occurs when the excitation wavelength is: 
 Options:  <1> 100 nm higher than the emission wavelength. <2> 100 nm lower than the emission wavelength. <3> Same as the emission wavelength. <4> 100 nm greater than the excitation wavelength. <5> 100 nm less than the excitation wavelength.
Output: 3
Question: The molar absorption coefficient of a compound: 
 Options:  <1> It has dimensions of M-1 cm-1, it is constant at a specific wavelength and in a particular solvent. <2> Its dimensions are mol L-1 cm-2 and it is constant at a given wavelength and in a given solvent. <3> It has dimensions L mol-1 cm-3 and is constant throughout the spectral region and is not influenced by the solvent. <4> Its dimensions are Photons per mole and it varies with the wavelength and with the solvent. <5> It is dimensionless, constant and does not vary with the wavelength or with the solvent.
Output: 1
Question: Capillary isotachophoresis (CITP) separates: 
 Options:  <1> Cations but can not separate anions. <2> Anions but can not separate cations. <3> Cations and anions simultaneously. <4> Cations and anions but not simultaneously. <5> Only neutral molecules.
Output: 4
Question: Could a glass electrode be used as a reference electrode ?: 
 Options:  <1> Yes, if the glass electrode is a combined electrode. <2> Yes, if a mercury electrode is used as the indicator electrode. <3> No, since the glass electrode is a selective electrode. <4> No, because its foundation is not Nerstian. <5> Yes, if the determination is made in a buffered medium.
Output: 5
Question: In the analysis of arsenic by graphite chamber losses of said element can be produced by volatilization during the carbonization stage. This fact can be minimized if: 
 Options:  <1> We raise the temperature during the carbonization stage. <2> We increase the carbonization time. <3> We add matrix modifiers that thermally stabilize the analyte. <4> We lower the temperature during the carbonization stage. <5> We modified the drying program to completely vaporize the solvent.
Output: 3
Question: If we value 25 mL of an H2A acid in concentration 0.1000M (pKa1 = 5, pKa2 = 9) with NaOH, the pH when we have evaluated 50% of the initial acid will be: 
 Options:  <1> one. <2> 3. <3> 5. <4> 7 <5> 9
Output: 3
Question: A biosensor consists of: 
 Options:  <1> A receiver, a transducer, and an enzymatic brand. <2> A receptor and an enzymatic brand. <3> A transducer and an enzymatic brand. <4> A receiver and a transducer. <5> A receptor and an antibody.
Output: 4
Question: The chloride present in a solution can be determined volumetrically, by the Mohr method, using Ag (I) as a reagent. What indicator is used in this assessment ?: 
 Options:  <1> K2Cr2O7. <2> Fe2 (SO4) 3. <3> K2CrO4. <4> KSCN <5> FeSO4.
Output: 3
Question: In the kinetic methods of analysis: 
 Options:  <1> Slow reactions can be used. <2> It is necessary that the reaction be completed in order to obtain the data of the equilibrium concentrations. <3> Low concentrations of a catalyst can be determined as long as the speed of the reaction does not depend on the concentration thereof. <4> It is not necessary to rigorously control the experimental conditions. <5> Mixtures of analytes can be determined as long as they all react with the same reagent at the same reaction rate.
Output: 1
Question: In the evaluation of a base with hydrochloric acid, it is known that the equivalence point appears at pH 5.54. If the bromocresol purple is used as indicator, whose turning interval is 5.2-6.8, the end point is observed at pH: 
 Options:  <1> 6.0, with a small error by default. <2> 6.8, with an error by excess. <3> 5.2, with a small error for excess. <4> 5.54. There is no error <5> 6.0, with an error for excess.
Output: 3
Question: Clark's electrode is based on: 
 Options:  <1> Potentiometric. <2> Potentiostatic <3> Optical. <4> Amperometric. <5> Conductimetric
Output: 4
Question: A coulometric evaluation: 
 Options:  <1> You do not need the current performance to be 100%. <2> It does not need an indicator system of the end point. <3> Always use a potentiostatic system. <4> It uses a titrant that is generated electrolytically. <5> You need a burette to add the titrant.
Output: 4
Question: A basic component of spectrophotometers is the monochromator. Its function is: 
 Options:  <1> Connect the different wavelengths from the source to achieve greater light power. <2> Transform the optical signal measured by the detector into an electrical signal. <3> Disperse the light separating the wavelengths that compose it and select a narrow band. <4> Amplify the analytical signal by improving the signal-to-noise ratio. <5> Decrease the power of the light beam to eliminate the background noise of the spectrophotometer.
Output: 3
Question: Turbidimetry and nephelometry are non-spectroscopic techniques based on the dispersion of light, with interesting applications in biochemical analysis. The criteria to be taken into account when choosing between nephelometry and turbidimetry in the analysis of a sample containing particles in suspension are: 
 Options:  <1> The size of the suspended particles and the detector of the instrument. <2> The size of the suspended particles and the wavelength of the radiation used. <3> The wavelength of the radiation emitted and the shape of the suspended particles. <4> The size of the suspended particles and the color of them. <5> The color of the particles and their fluorescence.
Output: 2
Question: In chemiluminescent measurements, the analyte to be determined must first pass to the excited state by: 
 Options:  <1> Absorption of electromagnetic radiation. <2> Emission of electromagnetic radiation. <3> A chemical reaction <4> Radio waves. <5> Sound waves.
Output: 3
Question: When carrying out the validation of an analytical method it is necessary to take into account the following basic aspects: 
 Options:  <1> Validate the analytical process as a whole, the range of concentrations in which it is applied, as well as the method in a single matrix to ensure selectivity. <2> Validate the previous stages of treatment of the sample, the range of concentrations in which it is applied and the method in a single matrix to ensure the selectivity. <3> Validate the final measurement method, validate the range of low concentrations (traces) in which it is applied and the method in a single matrix to ensure sensitivity. <4> All that is required is to validate the instrumentation by means of suitable calibrations. <5> Validate the analytical process as a whole, the concentration interval in which it is applied and the method in each of the matrices to which it will be applied.
Output: 5
Question: If an analytical method allows to determine 1 ppm of Pb, we are referring to: 
 Options:  <1> 1 mg / L. <2> 1 mg / mL. <3> 1 μg / L. <4> 1 ng / L. <5> 1 ng / mL.
Output: 1
Question: The alkaline error that occurs in glass electrodes for the average pH: 
 Options:  <1> It is due to the presence of an excessive concentration of protons that is replaced by sodium ions in the glass membrane. <2> Occurs at neutral pH due to the absence of protons. <3> It takes place at very alkaline pH, in which the sodium ion behaves as if it were a proton. <4> It appears as a consequence of the dehydration of the glass membrane. <5> It occurs when the electrode is introduced into pure water due to the dissolution of the sodium ions in the membrane.
Output: 3
Question: Temperature is one of the important variables in the emission techniques, because: 
 Options:  <1> The energy emitted by the atoms varies exponentially with it. <2> The population of atoms in the excited state decreases when it increases. <3> The population of atoms in the excited state increases when it decreases. <4> By increasing the atoms evaporate and the analytical signal decreases. <5> When increasing it increases the power of the electromagnetic radiation coming from the hollow cathode lamp.
Output: 1
Question: A primary standard solution in a titration should not: 
 Options:  <1> Be prepared from a high purity reagent. <2> Have an exactly known concentration. <3> Keep your composition over time. <4> React instantly. <5> Give rise to secondary reactions.
Output: 5
Question: A classification of gas chromatography detectors commonly found in the literature divides them into concentration and mass detectors, destructive and non-destructive, integral or differential and universal or selective. According to this classification: 
 Options:  <1> The thermal conductivity detector is a selective detector. <2> The flame ionization detector responds to the concentration of the analyte. <3> The thermal conductivity detector responds to the concentration of the analyte. <4> The phosphorus and nitrogen detector (NPD) is a universal detector. <5> The thermocalorimeter detector is of the differential type.
Output: 3
Question: The method of continuous variations is used in molecular absorption spectrophotometry to: 
 Options:  <1> Determine the position of the isobestic point in a mixture of absorbent species. <2> Calculate the exact position of the absorption maximum of an absorbent complex. <3> Obtain the pH corresponding to the end point of the titration of an absorbing acid or base. <4> Calculate the stoichiometry of an absorbent complex. <5> Calculate the exact value of the dissociation constant of an absorbent acid.
Output: 4
Question: A potentiometric titration is always done at i = 0: 
 Options:  <1> Yes, because that is where the Nernst equation is fulfilled. <2> Yes, because it is an instrumental requirement. <3> No, because there are potentiometric titrations at constant i. <4> No, because potentiometric titrations are never made at i = 0. <5> Yes, as long as an indicator electrode and a reference electrode are used.
Output: 3
Question: In the technique of analysis by injection in flow: 
 Options:  <1> A relatively large volume of sample is injected into the system, obtaining signals at steady state. <2> A small volume of sample whose integrity is maintained by segmentation with air bubbles is introduced. <3> The sample maintains its integrity throughout the process as it is available in separate containers. <4> The responses obtained have a peak shape whose height depends on the concentration of the sample. <5> The main difficulty lies in the slowness of the measures.
Output: 4
Question: The determination of dissolved oxygen in natural water samples, using the Winkler method, is based on the previous oxidation of Mn (II) in an alkaline medium to: 
 Options:  <1> Mn (IV). <2> Mn (VI) <3> Mn (VII). <4> Mn (V). <5> Mn (I).
Output: 1
Question: The spectrum of Circular Discipism of a molecule gives information about: 
 Options:  <1> The isosbestic point. <2> The isoelectric point. <3> Optically active chromophores. <4> Functional groups. <5> Molecular weight.
Output: 3
Question: In an electrogravimetric analysis: 
 Options:  <1> The increase in mass of the electrode indicates the amount of analyte. <2> Current performance must be 100%. <3> A platinum mesh is always used as a working electrode. <4> A reference electrode is always needed. <5> The solution does not need to be conductive.
Output: 1
Question: In the determination of water hardness due to the presence of Ca2 + and Mg2 + ions, the titrant reagent is used: 
 Options:  <1> Methyl orange. <2> A standard solution of potassium chloride. <3> Black Eriochrome T. <4> A standard solution of ethylenediaminetetraacetic acid (EDTA). <5> A solution of AEDT previously standardized against a solution of potassium phthalate.
Output: 4
Question: The solubility of calcium fluoride in a solution of pH <3 is higher than in pure water due to: 
 Options:  <1> The absence of reactions of formation of hydroxylated calcium complexes at these pH values. <2> The lower hydration capacity of the precipitate particles at these pH values. <3> The absence of reactions of formation of soluble complexes of calcium and fluoride at these pH values. <4> The complex formation reactions of the Ca2 + ion with the hydronium. <5> The protonation reaction of the fluoride anion.
Output: 5
Question: A cyclic voltammetry: 
 Options:  <1> It is based on a stationary broadcasting regime. <2> It uses macroelectrodes as working electrodes. <3> He never needs a potentiostatic system. <4> It is always done in a non-agitated solution. <5> It uses a square wave potential format as an excitation system.
Output: 4
Question: When you want to analyze the volatile components of a liquid or solid sample by gas chromatography, a headspace methodology (HS-GC) is usually used. In its static form: 
 Options:  <1> An aerosol is generated on the solid samples by passing a gas flow over it, which causes the transfer of volatile compounds to it. After a while, a volume of this gas is introduced into the column. <2> It is used to analyze a liquid in contact with a gas, by injecting a small volume of liquid into the head of the column. <3> The sample is placed in a vial with a volume of gas above, closed and thermostatted. Once the equilibrium between the two phases is reached, an aliquot of gas is introduced into the stream of the carrier gas that goes to the column. <4> The sample in liquid form is placed in a vial and closed. After a while, the same is opened so that the volatile components are balanced with those of the environment and subsequently, a volume of the gas surrounding the chromatograph is introduced. <5> An extraction of the liquid or solid sample is carried out to a gas that flows on it continuously.
Output: 3
Question: In the valuation of a strong base with a strong acid the pH of the equivalence point: 
 Options:  <1> It depends on the strong base that is valued. <2> It is determined by the excess OH ̄ of the solution. <3> It depends on the strong acid used as a titrant. <4> It is determined by the dissociation of water. <5> It is determined by the excess H + of the solution.
Output: 4
Question: Reactions in which there are no intermediates are described as: 
 Options:  <1> Concerted. <2> Polar <3> Radicals <4> Homolitic <5> Heterolithic
Output: 1
Question: The number of signals in the 13 C NMR spectrum of cis-1,2 dimethylcyclopentane with proton decoupling is: 
 Options:  <1> Three. <2> Four. <3> Five. <4> Six. <5> Seven.
Output: 2
Question: Which of the following alcohols has the lowest pKa value ?: 
 Options:  <1> Ethanol. <2> 2-Chloroethanol. <3> 2-Propanol. <4> 2,2,2-Trifluoroethanol. <5> 1,1-Dimethylethanol.
Output: 4
Question: Neighboring halohydrins, when treated with a base, are easily transformed into: 
 Options:  <1> Dioles <2> Alquenos <3> Alcohols <4> Epoxides <5> Ketones
Output: 4
Question: The Wittig reaction is one of the most important processes to obtain: 
 Options:  <1> Alquenos <2> Alcanes. <3> Ketones <4> Ethers <5> Nitriles
Output: 1
Question: The arenio ion is a reaction intermediate that is formed in the reactions of: 
 Options:  <1> Electrophilic addition. <2> Electrophilic aromatic substitution. <3> Nucleophilic substitution. <4> Nucleophilic addition. <5> Aromatic nucleophilic substitution.
Output: 2
Question: Organomagnesium compounds are commonly referred to as: 
 Options:  <1> Lipshutz <2> Birch. <3> Grignard. <4> Noyori <5> Blanc.
Output: 3
Question: Dimethyl sulfoxide (DMSO): 
 Options:  <1> It is a protic polar solvent. <2> It is a polar aprotic solvent. <3> It is not a solvent. <4> It is a colorless solid. <5> None of the above.
Output: 2
Question: The reaction of 5-Decino with sodium in ammonia and tert-butanol produces: 
 Options:  <1> Dean. <2> cis-5-Decene. <3> 5-Decanamin. <4> trans-5-Decene. <5> 5,6-Decanodiamine.
Output: 4
Question: The coupling of a terminal alkyne with vinyl halide by palladium catalysis is known as the reaction of: 
 Options:  <1> Heck <2> Suzuki <3> Sonogashira. <4> Stille <5> Nicolaou
Output: 3
Question: The NR3 group of a quaternary ammonium salt, R ̶ NR3, is a good leaving group in reactions: 
 Options:  <1> E1. <2> E2. <3> SN1. <4> SN2. <5> In none of the above.
Output: 2
Question: The reaction of ethyl acetate and acetone in the presence of sodium hydride in diethyl ether generates, after hydrolysis: 
 Options:  <1> 2,4-Pentanedione. <2> 4-Methyl-3-penten-2-one. <3> 3-Oxobutanoate of ethyl. <4> 2,3-Pentanedione. <5> 4-Hydroxy-4-methyl-2-pentanone.
Output: 1
Question: The reaction of Wolff-Kishner is one: 
 Options:  <1> Oxidation of carbonyls to give acids. <2> Reduction of carbonyls to alcohols. <3> Deoxygenation of carbonyls that takes place in an acid medium. <4> Deoxygenation of carbonyls that is carried out in an alkaline medium. <5> Carbonyl deoxygenation performed in neutral medium.
Output: 4
Question: The reaction of cyclopentene with an aqueous solution of bromine at 0 ° C originates: 
 Options:  <1> trans-1,2-dibromocyclopentane. <2> cis-2-bromocyclopentanol. <3> trans -2-bromocyclopentanol. <4> trans -1,2-cyclopentanediol. <5> cis-1,2-dibromocyclopentane.
Output: 3
Question: The Chichibabin reaction is an example of nucleophilic substitution in a ring of: 
 Options:  <1> Benzene. <2> Anthracene <3> Biphenyl <4> Pyridine <5> Pirrol.
Output: 4
Question: In the reaction of methoxybenzene with acetic anhydride and aluminum trichloride followed by treatment with an aqueous solution of hydrochloric acid is formed mainly: 
 Options:  <1> 4-methoxybenzoic acid. <2> 1- (4-methoxyphenyl) ethanone. <3> 1- (3-methoxyphenyl) ethanone. <4> 3-methoxybenzoic acid. <5> 4-methoxyphenyl acetate.
Output: 2
Question: The major product of the reaction of 2-methylcyclohexanol with HBr is: 
 Options:  <1> 1-Bromo-2-methylcyclohexane. <2> Methylcyclohexane <3> 1-Bromo-1-methylcyclohexane. <4> 1-Methylcyclohexane. <5> Cyclohexane
Output: 3
Question: The lithium aluminum hydride is a nucleophile strong enough to be added to the carbonyl group of the carboxylate ions. This process allows obtaining: 
 Options:  <1> Primary alcohols. <2> Secondary alcohols <3> Tertiary alcohols. <4> Ketones <5> Ethers
Output: 1
Question: The reaction between a ketone and a Grignard reagent causes, after hydrolysing the salt formed, a: 
 Options:  <1> Carboxylic ester. <2> Alcohol. <3> Ether. <4> Aldehyde. <5> Carboxylic acid.
Output: 2
Question: In the aromatic electrophilic substitution with a monosubstituted benzene ring, the halogens are: 
 Options:  <1> Ortho / for leaders but activating. <2> Target leaders but activating. <3> Goal / for leaders but activating. <4> Ortho / goal leaders but activating. <5> Ortho / for leaders but deactivators.
Output: 5
Question: The reaction of 1H-indole with electrophiles takes place selectively on the atom in position: 
 Options:  <1> one. <2> two. <3> 3. <4> Four. <5> 5.
Output: 3
Question: The enolate ions undergo conjugate addition to α, β-unsaturated aldehydes and ketones, a reaction known as: 
 Options:  <1> Addition of Michael. <2> Addition of Prins. <3> Transposition of Cope. <4> Radical addition. <5> Transposition of Beckman.
Output: 1
Question: The heating of trans, cis, trans-2,4,6octatriene results in: 
 Options:  <1> trans, trans, trans-2,4,6-Octatriene. <2> cis, cis, cis-2,4,6-Octatriene. <3> There is no reaction. <4> trans-5,6-Dimethyl-1,3-cyclohexadiene. <5> cis -5,6-Dimethyl-1,3-cyclohexadiene.
Output: 5
Question: The reaction conditions for the preparation of 2-methyl-2-methoxypropan-1-ol from 2,2-dimethyloxirane are: 
 Options:  <1> Methanol in acid medium. <2> Lithium aluminum hydride in methanol. <3> Methylmagnesium bromide and subsequent hydrolysis. <4> Sodium methoxide in methanol. <5> Triphenylphosphine in methanol.
Output: 1
Question: The stabilizing effect of the alkyl groups on the adjacent π bonds is explained in terms of: 
 Options:  <1> Isomería. <2> Mesomería. <3> Inductive effect <4> Hyperconjugation. <5> Stereoisomería.
Output: 4
Question: The reaction product of cyclohexanone with bromine catalyzed by a base is: 
 Options:  <1> 2-Bromocyclohexanone. <2> 2,2-Dibromocyclohexanone. <3> 2,2,6-Tribomociclohexanona. <4> 1,1-Dibromocyclohexane. <5> 2,2,6,6-Tetrabromocyclohexanone.
Output: 5
Question: Of the following reaction mechanisms, in which there is an inversion of the configuration from the reactant to the product of the reaction ?: 
 Options:  <1> Bimolecular nucleophilic substitution (SN2). <2> Unimolecular elimination (E1). <3> Unimolecular nucleophilic substitution (SN1). <4> Addition Markovnikov. <5> Addition anti-Markovnikov.
Output: 1
Question: The systematic nomenclature rules of the IUPAC give priority as a main function, from among the following functional groups, to: 
 Options:  <1> Amines <2> Carboxylic acids. <3> Nitriles <4> Carboxylic ethers. <5> Aldehydes.
Output: 2
Question: The aldol condensation gives rise to: 
 Options:  <1> Α, β-unsaturated amides. <2> Saturated amides. <3> Α, β-unsaturated carbonyl compounds. <4> Chiral compounds. <5> Β, γ-unsaturated carbonyl compounds.
Output: 3
Question: By reaction of carbonyls with primary and secondary amine, the following are obtained: 
 Options:  <1> Iminas and oximes. <2> Iminas and enaminas. <3> Oxazones and hydrazones. <4> Semicarbazones and nitrones. <5> None of the above.
Output: 2
Question: A compound that has a five-membered aromatic heterocyclic skeleton with three carbon atoms and two nitrogens, the latter being positions 1 and 3, is called: 
 Options:  <1> Pirrol. <2> Pyrimidine <3> Pyrazole <4> Pyrazolidine. <5> Imidazole
Output: 5
Question: In mass spectrometry, the most common fragmentation pattern is the break in α, which cleaves the alkyl bond adjacent to the carbonyl to give: 
 Options:  <1> The corresponding acyl cation and an alkyl radical. <2> The corresponding acyl anion and an alkyl radical. <3> The corresponding acyl radical and an alkyl radical. <4> The corresponding acyl cation and an alkyl cation. <5> The corresponding acyl anion and an alkyl anion.
Output: 1
Question: Which of the following compounds has more basic character ?: 
 Options:  <1> Sodium hydroxide. <2> Sodium ethoxide <3> Sodium amide <4> Sodium bicarbonate. <5> Sodium carbonate.
Output: 3
Question: The reordering of Cope is a reordering: 
 Options:  <1> From an allyl vinyl ether. <2> [1,3] -sigmatropic. <3> [1,2] -sigmatropic. <4> [3,3] -sigmatropic. <5> It is a cycloaddition [4 + 2].
Output: 4
Question: A very important industrial method for the formation of carbon-nitrogen bonds is the transposition of Beckman, a reaction that transforms: 
 Options:  <1> A ketone in a pyridine. <2> An oxime in an amine. <3> An aldehyde in an amide. <4> A ketone in an amide. <5> An oxime in an amide.
Output: 5
Question: Sodium borohydride is a reagent used in Organic Chemistry for its properties such as: 
 Options:  <1> Reducer. <2> Oxidizer <3> Alkylator <4> Acid. <5> Organometallic.
Output: 1
Question: The reaction of an alkene with metachloroperbenzoic acid causes a cyclic ether which is called: 
 Options:  <1> Furano <2> Dioxane <3> Epoxide <4> Azirano <5> Lactone
Output: 3
Question: The type of membrane transport that uses ionic gradients as an energy source is: 
 Options:  <1> Facilitated dissemination. <2> Passive transport <3> Primary active transport. <4> Secondary active transport. <5> Simple diffusion.
Output: 4
Question: Which of the following covalent bonds does not appear in proteins ?: 
 Options:  <1> Phosphodiester linkage. <2> Amide link. <3> O-glucosidic bond. <4> Disulfide bond. <5> Hydrogen bond.
Output: 1
Question: A promoter place in the DNA: 
 Options:  <1> Transcribe the repressor. <2> Start the transcription. <3> It encodes the RNA polymerase. <4> Regulate the termination. <5> Translate specific proteins.
Output: 2
Question: Which of the following compounds can not serve as a precursor for the synthesis of glucose via gluconeogenesis ?: 
 Options:  <1> Acetate. <2> Glycerol <3> Lactate <4> Oxalacetate. <5> α-ketoglutarate.
Output: 1
Question: The first step in the folding of disordered polypetide chains is: 
 Options:  <1> Formation of the primary structure. <2> Formation of disulfide bridges. <3> Formation of aggregates. <4> Post-translational modifications. <5> Formation of secondary structure elements.
Output: 5
Question: What RNA eukaryotic polymerase is involved in the transcription of messenger RNA (mRNA) ?: 
 Options:  <1> RNA Polymerase I. <2> RNA Polymerase II. <3> RNA Polymerase III. <4> RNA Polymerase IV. <5> Transcription of mRNA is carried out jointly by RNA Polymerase I and RNA Polymerase II.
Output: 2
Question: Which of the following enzymes catalyzes phosphorylation using inorganic phosphate: 
 Options:  <1> Hexokinase. <2> Fosfofructoquinasa. <3> Glyceraldehyde-3-phosphate dehydrogenase. <4> Phosphoglycerate kinase. <5> Pyruvate kinase.
Output: 3
Question: Which of the following statements is NOT true about glucagon ?: 
 Options:  <1> Activates hepatic glycogenesis. <2> Activates lipolysis in white adipose tissue. <3> Activates hepatic glycogenolysis. <4> It is a polypeptide. <5> It is synthesized in the α cells of the islets of Langerhans of the pancreas.
Output: 1
Question: How are the proteins involved in the DNA curl and compaction called ?: 
 Options:  <1> Kinases <2> Topoisomerases <3> Histones. <4> Phosphatases <5> DNA nucleases
Output: 3
Question: Insulin regulates the synthesis of fatty acids: 
 Options:  <1> Activating phosphorylase <2> Dephosphorylating acetyl CoA carboxylase. <3> Inhibiting the formation of malonyl CoA. <4> Controlling the carnitine-acyl CoA transferase activity. <5> Activating the fatty acid synthetase.
Output: 2
Question: Oxidative phosphorylation involves: 
 Options:  <1> The oxidation of H2O to form O2. <2> Oxidation of O2 to form H2O. <3> The reduction of H2O to give O2. <4> The reduction of O2 to give H2O. <5> None of the above.
Output: 4
Question: Glycogenin: 
 Options:  <1> It catalyzes the conversion of starch into glycogen. <2> It is the enzyme responsible for the formation of branches in glycogen. <3> It is the gene that codes for glycogen synthase. <4> It is the primer on which new chains of glycogen start. <5> Regulates glycogen synthesis.
Output: 4
Question: The altered or minority nitrogenous bases: 
 Options:  <1> They are not detected in DNA. <2> They are not detected in the RNA. <3> They protect genetic information. <4> They are not detected in the tRNA. <5> They are not able to mate.
Output: 3
Question: The precursor of all the pyrimidine nucleotides of the cell is: 
 Options:  <1> Uridine monophosphate (UMP). <2> Thymidine monophosphate (TMP). <3> Cytidine monophosphate (cmp). <4> Inosine monophosphate (IMP). <5> Guanidine monophosphate (GMP).
Output: 1
Question: All the following statements describe characteristics of the peptide link EXCEPT: 
 Options:  <1> It has a trans configuration. <2> It is polar but without charge. <3> It forms a single bond by directly joining the α carbons of adjacent amino acids. <4> It does not present rotation around the link. <5> Is flat.
Output: 3
Question: CO is toxic to aerobic organisms: 
 Options:  <1> Because it oxidizes the OH groups of the hemoglobin, preventing it from being able to fix O2 correctly. <2> Because it enters the mitochondria, picking up electrons from the transport chain with less efficiency than O2. <3> Because it joins the heme group with greater affinity than O2. <4> Because having a greater dipolar character, is more soluble than O2 in blood and blocks the exchange of O2 between air and blood at the level of the lungs. <5> None of the above is correct.
Output: 3
Question: Pyridoxal phosphate is a prosthetic group of enzymes involved in reactions of: 
 Options:  <1> Acetylation <2> Desulfation. <3> Methylation <4> Reduction. <5> Transamination.
Output: 5
Question: Which of the following compounds in a fundamental intermediate of the synthesis of triacylglycerols and phospholipids: 
 Options:  <1> CDP-choline. <2> Phosphatidate <3> Triglyceride <4> Phosphatidylserine <5> CDP-diacylglycerol.
Output: 2
Question: At neutral pH, a mixture of amino acids in solution would be predominantly: 
 Options:  <1> Dipolar Ions <2> Non-polar molecules. <3> Positive and monovalent. <4> Hydrophobic <5> Negative and monovalent.
Output: 1
Question: Phosphatidylinositols: 
 Options:  <1> They are derivatives of glucocerebrosides. <2> They act as intracellular signals. <3> They are lysosomal lipids. <4> They are biological detergents. <5> They contain taurine or glycine.
Output: 2
Question: During oxidative phosphorylation, the proton-motor force generated by electronic transport is used to: 
 Options:  <1> Create a pore in the inner mitochondrial membrane. <2> Generate substrates (ADP and Pi) for ATP synthase. <3> Induce a conformational change in the ATP synthase. <4> Oxidize NADH to NAD +. <5> Reduce O2 to H2O.
Output: 3
Question: Indicate which of the following statements is true about bilirubin: 
 Options:  <1> It is a catabolic product of the heme group. <2> It is a product of the urea cycle. <3> It is an intermediary of the Krebs cycle. <4> It is a precursor of hepatic gluconeogenesis. <5> It is a product of cholesterol degradation.
Output: 1
Question: Which of the following statements about sphingolipids is CERTAIN: 
 Options:  <1> They may have charge, but they are not amphipathic molecules. <2> They are formed by glycerol and fatty acids. <3> They contain two esterified fatty acids. <4> The cerebrosides and ganglosides are sphingolipids. <5> Terpenes are the main sphingolipids.
Output: 4
Question: In the β-oxidation of odd-chain fatty acids, what is the molecule that forms with the last three carbons to enter the citric acid cycle ?: 
 Options:  <1> Propionyl-CoA. <2> Methylmalonyl-CoA. <3> Succinyl-CoA. <4> Succinate <5> Malate.
Output: 3