This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 86101. |
According to Faraday's laws of electrolysis, the discharge of one electrochemical equivalent of ions should involve |
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Answer» 1 mole of ELECTRONS |
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| 86102. |
According to Faraday's first Law of electrolysis mass of substance liberated is equal to |
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Answer» eC |
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| 86103. |
According to Fajan's rule polarisationis more when: |
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Answer» SMALL CATION and LARGE anion |
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| 86104. |
According to Ellingham diagram, the oxidation reaction of carbon to carbon monoxide may be used to reduce which one of the following oxides at the lowest temperature ? |
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Answer» `Al_(2)O_(3)` `Cu_(2)O+C to 2Cu+CO` |
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| 86105. |
According to Ellingham diagram, the oxidation reaction on the carbon to carbon monoxide may be used to reduce which one of the following oxides at the lowest temperature ? |
| Answer» ANSWER :B | |
| 86106. |
According to Ellingham diagram , the oxidation reaction of carbon to carbon monoxide may be used to reduce which one of the following oxides at lowest temperature ? |
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Answer» `Al_2O_3` |
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| 86107. |
Accordingto Ellingham diagram,theoxidationreactionofcarbontocarbonmonoxidemaybe used toreducewhichone ofthefollowingoxides atthelowesttermperature ? |
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Answer» ` Al_ 2O _ 3` |
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| 86108. |
According to Ellingham diagram Cr_(2)O_(3) reduced by |
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Answer» Al |
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| 86109. |
According to electromagnetic theory of radiation s in photo electric effect which of these statement is incorrect ? |
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Answer» only those radiations will be ABLE to emit electrtrons from the metal surface WHOSE frequaency is greater than threshold FREQUENCY |
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| 86110. |
According to electrochemical theory the metal which rusting take place as a result of |
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Answer» HYDROLYSIS |
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| 86111. |
According to electrochemical mechlanism for corrosion, the metal undergoing corrosion acts as |
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Answer» cathode `Fe(s) rarr Fe^(2+)(aq.)+2e^(-)` We can predict that active metals, which are low oin the `emf` series, should be most susceptible to corrosion. Cesium `(Cs)` and rubidium `(Rb)`, whicha re toward the bottom of the `emf` series, corrode very quickly in MOIST air. Other metals near the bottom of the `emf` seriesusually are STORED away from air, to prevent the swift corrosion that occurs when they come in contact with the atmosphere for any period of time. However, there are exceptions to this role as some active metals like `Al` corrode quite slowly because they form protective oxide conatings. Given an oxidation, there must be a reduction to consume the ELECTRONS released in the anode process. Some of the importment cathode, or reduction, half-reaction in corrosion are `2H^(+)(aq.)+2e^(-) rarr H_(2)(g) ["acid solution"]` `O_(2)(g)+4H^(+)(aq.)+4e^(-) rarr 2H_(2)O(l) ["acid solution"]` `O_(2)(g)+2H_(2)O(l)+4e^(-) rarr 4OH^(-)(aq.) ["neutral or alkaline solution"]` The standard potential of the half-reations in which dissolved `O_(2)` is reeduced are positive,so these reduction are more favorable than those involving `H^(+)` or `H_(2)O` alone. Metals corrode faster aat higher partial pressures of oxygen. because more `O_(2)` then dissolves into the layer of moisture that is in contact with the metal. There is an interesting aspect of corrosion called the principle of differential aeration: If a part of a metal surface is exposed to a relatively high concentration of `O_(2)`, corrosion occurs in anothr region of the metal. The potential DIFFERENCE that leads to corrosion requires the physical separation of the oxidation and reduction process in corrosion, which is the reduction of `O_(2)`, occurs in the region where the concentration of `O_(2)` is highest. Therefore the oxidation half-reaction which does the real damage, takes place elsewhere. In case of iron, the `Fe^(2+)` cations tht form migrate toward the cathodic regions of the metal surface. There they react with water or `OH^(-)` to form `Fe(OH)_(2)`, which undergoes further oxidation to form `Fe(OH)_(3)`, the familiar reddis material called rust. Menshile, the anodic region of the metal surface undergoes the real damage: Holes appear, the surface is eaten away, and the metal's structural strength is wakened. The worst damage seems to occur when the reduction process liberates `H_(2)(g)`, apparently because this gas penetrates below the surface and further weakens the metal. The corrosion of an automoblie a familiar demonstration of the principle of differential aeration. When some of the paint that protects the metal of the automobile chips off, corrosion does not occur at the site of the chipping, Rust does form at this spot, becuase it is the place where the reduction half-reaction occurs. The real damage is done at the anode region, which is a site near the exposed area. We can also demonstrate corrosion by differential aeration by embeddingmetal rods in sand, leaving the upper part of the rods in water. It is the segment of the rod in the sand that corrodes, not the segment in the water. The sand prevents corrodes, not the segment in the water. The sand prevents `O_(2)` from REACHING the metal. The reducing occurs in the oxygen-rich water while the damaging oxidation process occurs in the sand. A metal can corrode if the potential of the half-reaction for its oxidation is relatively more positive than any other oxidation that can occur when it is exposed is the basis of several methods for preventing corrosion. |
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| 86112. |
According to Dulong and Petit's rule, in case of solid elements. Approximate atomic mass =(6.4)/("specific heat") In this rule, specific heat is in |
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Answer» `KJ kg^(-1)K^(-1)` |
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| 86113. |
According to Debye-Huckel-Onsager equation,wedge_(m)^(c)=_____. |
| Answer» SOLUTION :`wedge_(m)^(C)=wedge_(m)^(@)-Asqrt(c)` | |
| 86114. |
According to de Broglie, matter has a wave character. still we cannot measure the wavelength of even 1 mg mass. It is because: |
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Answer» actually it does not have a wave CHARACTER |
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| 86115. |
According to cystal field theory, interaction between central metal atom/ion and ligand is electrostatic in nature. In free metal ions, the five d-orbitals are degenerate. However, in a ligand field e.g., tetrahedral, octahedral, square planar, square pyramidal, trigonal bipyramidal, the degeneracy of 5d-orbitals is lost. If lobes of d-orbitals of central metal atom/ion are along the axes through which ligands are approaching, the energy of corresponding d-orbital is raised more than the d-orbitals having lobes between teh axes. e.g., octahedral complexes, square planar complexes, square pyramidal compexes. The correct order Delta_(o), Delta_(t)" and "Delta_(sp) (where o, t and sp stand for octahedral, tetrahedral and square planar fileds respectively) is : |
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Answer» `Delta_(o) gt Delta_(SP) gt Delta_(t)` |
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| 86116. |
According to cystal field theory, interaction between central metal atom/ion and ligand is electrostatic in nature. In free metal ions, the five d-orbitals are degenerate. However, in a ligand field e.g., tetrahedral, octahedral, square planar, square pyramidal, trigonal bipyramidal, the degeneracy of 5d-orbitals is lost. If lobes of d-orbitals of central metal atom/ion are along the axes through which ligands are approaching, the energy of corresponding d-orbital is raised more than the d-orbitals having lobes between teh axes. e.g., octahedral complexes, square planar complexes, square pyramidal compexes. Which of the following orbitals has the highest energy in square pyramidal ligand field ? |
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Answer» `d_(xy)` |
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| 86117. |
According to crystal field theory, the M-L bond in a complex is |
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Answer» PURELY ionic |
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| 86118. |
According to crystal field theory ,The bond between the ligand and central metal atom is __________ |
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Answer» Purely IONIC |
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| 86119. |
According to crystal field theory (CFT) : |
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Answer» order of increasing field strength of LIGANDS is : `F^(-)gtH_(2)OgtNH_(3)` |
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| 86120. |
According to combined gas law. |
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Answer» <P>`PV PROP ( 1)/( V ) ` |
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| 86121. |
According to collision thery |
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Answer» collisions are sufficiently violent |
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| 86122. |
According to collisiontheory Rate=P.Z_(AB)e^(-Ea)/(RT) What does P indicate in the equation ? |
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Answer» pressure |
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| 86123. |
According to collision theory of reaction rates |
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Answer» every collision between reactans leads to CHEMICAL reaction |
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| 86124. |
According to collision theory for determiningthe variation of rate of reaction with temperature the rate constant,k= Ae^(-Ea//RT). For most of the practical purposes A and E_(a[Arrhenius factor and Activation energy] are temperature independent. However they may vary slightly. Assuming the conditions given above answer the following questions. "If"A=K,T"and"E_(a)=K_(2)T^(2) and the given equation is still applicable where K_(1)"and" K_(2) are the constant and T represent temperature then which will be correct option? (P) The maximum value of k will be equal to A (Q) At lower temperature rate of reaction will increase with increase in temperature (R) At higher temperature, rate of reaction will decrease with increase in temperature |
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Answer» <P>All are true |
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| 86125. |
According to collision theory of reaction rates, the activation energy is |
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Answer» the energy GAINED by the molecule on COLLIDING with other molecules. |
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| 86126. |
According to collision theory: |
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Answer» Collisions are sufficiently violent |
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| 86127. |
According to collision theory, |
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Answer» collisions are sufficiently violent |
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| 86128. |
According to classification of aminoacids, lysine belongs to the following |
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Answer» ACIDIC AMINO acid |
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| 86129. |
According to CIP rule, the correct arrangment in order of decreasing priority is :- |
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Answer» `–OH GT –CH_(2)OH gt –CHO gt –COOH ` |
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| 86130. |
According to Charles's law : |
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Answer» `((DV)/(DT))_P = K` |
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| 86131. |
According to, Charle's law |
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Answer» <P>`(dV/dT)_(P)=K` |
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| 86132. |
According to Charles' law, at constant pressure 100ml of a given mass of a gas with 10^(@)C rise in temperature will become( ( 1)/( 273) = 0.00366) |
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Answer» 1.100.0366 `= 100 + 100 xx 10 xx 0.0036` `= 103.66` |
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| 86133. |
According to Charle's law |
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Answer» `((DV)/(dT))_(P)=K` |
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| 86134. |
According to C.F.T, attraction between the central metal ion and ligands in a complex is purely electrostatic. The transition metal which forms the central atom cation in the complex is regarded as a positive ion. It is surrounded by negative ligands or neutral molecules which have a lone apir of electrons, if the ligand is a neutral molecule such as NH_(3), the negative and of the dipole in the molecule is directed towards the metal cation. the electrons on the central metal ion are under repulsive forces from those on the ligands. thus the electrons occupy the d-orbitals remain away from the direction of approach ligands. Q. The value of 'x' in the complex H_(x)[Co(CO)_(4)] (on the basis of EAN rule), and geometry arround Co ion respectively is: |
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Answer» 1, SQUARE planar |
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| 86135. |
According to C.F.T, attraction between the central metal ion and ligands in a complex is purely electrostatic. The transition metal which forms the central atom cation in the complex is regarded as a positive ion. It is surrounded by negative ligands or neutral molecules which have a lone apir of electrons, if the ligand is a neutral molecule such as NH_(3), the negative and of the dipole in the molecule is directed towards the metal cation. the electrons on the central metal ion are under repulsive forces from those on the ligands. thus the electrons occupy the d-orbitals remain away from the direction of approach ligands. Q. The crystal field-spliting order for Cr^(3+) cation is octahedral field for ligands CH_(3)COO^(-),NH_(3),H_(2)O,CN^(-) is: |
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Answer» `CH_(3)COO^(-) LT H_(2)O lt NH_(3) lt CN^(-)` |
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| 86136. |
According to C.F.T, attraction between the central metal ion and ligands in a complex is purely electrostatic. The transition metal which forms the central atom cation in the complex is regarded as a positive ion. It is surrounded by negative ligands or neutral molecules which have a lone apir of electrons, if the ligand is a neutral molecule such as NH_(3), the negative and of the dipole in the molecule is directed towards the metal cation. the electrons on the central metal ion are under repulsive forces from those on the ligands. thus the electrons occupy the d-orbitals remain away from the direction of approach ligands. Q. Correct relationship between pairing energy (P) and C.F.S.E. (Delta_(o)) in |
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Answer» <P>`Delta_(o) LT P` |
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| 86137. |
According to CFT the energy of t_(2g) orbitals in an octahedral complex |
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Answer» DECREASE by `2/5Delta_0` |
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| 86138. |
According to bronstedconcept, the acids in the reaction : NH_3+H_2O=NH_4+OH^- are: |
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Answer» `NH_3` and `NH_4^+` |
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| 86139. |
According to Bronsted principle, an aqueous solution of HNO_(3) will contain |
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Answer» `NO_(2)^(-)` |
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| 86140. |
According to Bronsted-Lowry concept, the correct order of relative strength of bases follows the order |
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Answer» `CH_(3)COO^(-) gt Cl^(-) lt OH^(-)` Conjugate acid or `OH^(-)` is `H_(2)O` which is a weak acid conjugate acid of `CH_(3)COO^(-)` is `CH_(3)COOH` which is stronger than `H_(2)O`. While conjugate acid of `Cl^(-)` is HCL which is strongest out of there. so the order of relative strength of bases is `OH^(-) gt CH_(3)COO^(-) gt Cl^(-)`. |
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| 86141. |
According to Bronsted lowry, water is a/an |
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Answer» Base |
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| 86142. |
According to Bronsted-Lowry concept, base is a substance which is |
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Answer» A PROTON donor |
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| 86143. |
According to Bohr's theory the radius of electron in an orbit described by principal quantum number n and atomic number Z is proportional to: |
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Answer» `Z^2n^2` |
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| 86144. |
According to Bohr's theory the energy required for the transition of H atom from n=6 to n=8 state is |
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Answer» equal to the energy required for the transition from N=5 to n=7 state |
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| 86145. |
According to Bohr's theory, the angular momentum of an electron is 5 th orbit is |
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Answer» `1.0 h//pi` `:.` Angular momentum in 5TH orbit `=(5h)/(2pi)` `=2.5h//pi` |
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| 86146. |
According to Bohr's theory, the angular momentum for an electron of 5th orbit is |
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Answer» `10h//pi` |
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| 86147. |
According to Bohr's theory E_(n) =Total energy K_(n) =Kinetic energy V_(n) =Potential energyr_(n) = Radius of nth orbit Match the following : Column -IColumn -II (A)V_(n) //K_(n ) = ?( p ) 0 (B ) If radius of nth orbit propEn^(x) , x = ?( q)-1 ( C ) Angular momentum in lowest orbital ( r ) - 1 (D )( 1)/( r^(n)) prop Z^(4) , y = ?( s ) 1 |
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Answer» |
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| 86148. |
According to Bohr's theory, |
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Answer» when the atom gets the REQUIRED energy from the outside, electrons JUMP from LOWER orbits to higher orbits and remain there |
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| 86149. |
According to BIS, what is the per centage of TFM in bath Soap of grade - 3? |
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Answer» more than 65% but LESS than `76%` |
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| 86150. |
According to Bayer's strain theory which is highly stable? |
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Answer» Cyclobutane `d = (1)/(2)(109^(@)28'` - valency angle) In cyclobutane , `d = (1)/(2) (109^(@)28' - 90^(@)) = 9^(@)44'` In cyclopentane , `d = (1)/(2) (109^(@)28' - 108^(@)) = 0^(@)44'` In cyclohexane, `d = (1)/(2) (109^(@)28' - 120^(@)) = -5^(@)16'` In cycloheptane , `d = (1)/(2) (109^(@)28' - 135^(@)) = -9^(@)33'` Cyclopentane is more stable and LESS reactive compared to cyclobutane, and cyclohexane and cycloheptane are free from angle of strain.Therefore quite stable.But actually Bayer's theory fails for the rings containing six or more carbone ATOMS. |
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