question_answer2) Consider the ground state of\[Cr\]atom\[(Z=24)\]. The numbers of electrons with the azimuthal quantum numbers, \[l=1\] and 2 are, respectively
question_answer4) The wavelength of the radiation emitted, when in a hydrogen atom electron falls from infinity to stationary state 1, would be (Rydberg constant\[=1.097\times {{10}^{7}}\text{ }{{m}^{-1}})\]
question_answer6) Which one of the following sets of ions represents the collection of isoelectronic species? (At.\[nos.\,F=9,Cl=17,Na=11,Mg=12,\] \[Al=13,K=19,Ca=20,Sc=21)\]
question_answer9) The formation of the oxide ion\[{{O}^{2-}}(g)\]requires first an exothermic and then an exothermic step as shown below \[O(g)+{{e}^{-}}={{O}^{-}}(g);\] \[\Delta {{H}^{o}}=-142\,kJ\,mo{{l}^{-1}}\] \[{{O}^{-}}{{(g)}^{-}}+{{e}^{-}}={{O}^{2}}(g);\] \[\Delta {{H}^{o}}=844\,kJ\,mo{{l}^{-1}}\] This is because
A)
oxygen is more electronegative
doneclear
B)
oxygen has high electron affinity
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C)
\[{{O}^{-}}\]ion will tend to resist the addition of another electron
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D)
\[{{O}^{-}}\]ion has comparatively larger size than oxygen atom
question_answer13) As the temperature is raised from\[20{}^\circ C\]to \[40{}^\circ C,\]the average kinetic energy of neon atoms changes by a factor of which of the following?
question_answer19) \[6.02\times {{10}^{20}}\]molecules of urea are present in 100 mL of its solution. The concentration of urea solution is (Avogadro constant, \[{{N}_{A}}\,=6.02\,\times {{10}^{23}}\,mo{{l}^{-1}}\])
question_answer20) To neutralize completely 20 mL of 0.1M aqueous solution of phosphorous acid \[({{H}_{3}}P{{O}_{3}}),\]the volume of 0.1M aqueous KOH solution required is
question_answer21) For which of the following parameters the structural isomers\[{{C}_{2}}{{H}_{2}}OH\]and\[C{{H}_{3}}OC{{H}_{3}}\] would be expected to have the same values? (Assume ideal behaviour)
A)
Heat of vaporization,
doneclear
B)
Vapour pressure at the same temperature
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C)
Boiling points
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D)
Gaseous densities at the same temperature and pressure
question_answer24) What type of crystal defect is indicated in the diagram below?\[N{{a}^{+}},C{{l}^{-}},N{{a}^{+}},C{{l}^{-}},N{{a}^{+}},C{{l}^{-}}\] \[C{{l}^{-}}+C{{l}^{-}}N{{a}^{+}}+N{{a}^{+}}\]\[N{{a}^{+}}C{{l}^{-}}+C{{l}^{-}}N{{a}^{+}}C{{l}^{-}}\]\[C{{l}^{-}}N{{a}^{+}}C{{l}^{-}}N{{a}^{+}}+N{{a}^{+}}\]
question_answer25) An ideal gas expands in volume from \[1\times {{10}^{-3}}{{m}^{3}}\]to\[1\times {{10}^{-2}}{{m}^{3}}\]at\[300\text{ }K\]against a constant pressure of\[1\times {{10}^{5}}N{{m}^{-2}}\]. The work done is
question_answer27) In a first order reaction, the concentration of the reactant, decreases from 0.8 M to 0,4 M in 15 min, The time taken for the concentration to change from 0.1 M to 0.025 M is
question_answer30) The equilibrium constant for the reaction \[{{N}_{2}}(g)+{{O}_{2}}(g)2NO(g)\] at temperature T is \[4\times {{10}^{-4}}\]. The value of\[{{K}_{c}}\] for the reaction \[NO(g)\frac{1}{2}{{N}_{2}}(g)+\frac{1}{2}{{O}_{2}}(g)\]at the same temperature is
question_answer31) The rate equation for the reaction \[A+B\xrightarrow{{}}C\]is found to be rate\[=k[A][B]\] The correct statement in relation to this reaction is that the
A)
unit of k must be\[{{s}^{-1}}\]
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B)
\[{{t}_{1/2}}\]is a constant
doneclear
C)
rate of formation of C is twice the rate of disappearance of A
doneclear
D)
value of k is independent of the initial concentrations of A and B
question_answer32) Consider the following\[E{}^\circ \]values \[E{{{}^\circ }_{F{{e}^{3+}}/F{{e}^{2+}}}}=+0.77\,V\] \[E{{{}^\circ }_{S{{n}^{2+}}/Sn}}=-0.14\,V\] Under standard conditions the potential for the reaction \[Sn(s)+2F{{e}^{3+}}(aq)\xrightarrow{{}}2F{{e}^{2+}}(aq)\] \[+S{{n}^{2+}}(aq)\]is
question_answer33) The molar solubility (in\[mol\text{ }{{L}^{-1}}\]) of a sparingly soluble salt\[M{{X}_{4}}\]is 's'. The corresponding solubility product is\[{{K}_{sp}}\]. s as given in terms of \[{{K}_{sp}}\]by the relation
question_answer34) The standard emf of a cell, involving one electron change is found to be 0.591 V at\[25{}^\circ C\]. The equilibrium constant of the reaction is \[(F=96500\text{ }C\text{ }mo{{l}^{-1}})\]
question_answer35) The enthalpies of combustion of carbon and carbon monoxide are\[-393.5\]and\[-283\text{ }kJ\text{ }mo{{l}^{-1}}\]respectively. The enthalpy of formation of carbon monoxide per mole is
question_answer37) In a cell that utilises the reaction, \[Zn(s)+2{{H}^{+}}(aq)\xrightarrow{{}}Z{{n}^{2+}}(aq)+{{H}_{2}}(g)\] addition of\[{{H}_{2}}S{{O}_{4}}\]to cathode compartment, will
A)
lower the E and shift equilibrium to the left
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B)
lower the E and shift the equilibrium to the right
doneclear
C)
increase the E and shift the equilibrium to the right
doneclear
D)
increase the E and shift the equilibrium to the left
question_answer43) Aluminium chloride exists as dimer,\[A{{l}_{2}}C{{l}_{6}}\]in solid state as well as in solution of non-polar solvents such as benzene. When dissolved in water, it gives
question_answer44) The soldiers of Napolean army while at Alps during freezing winter suffered a serious problem as regards to the tin buttons of their uniforms. White metallic tin buttons got converted to grey powder. This transformation is related to
A)
a change in the crystalline structure of tin
doneclear
B)
an interaction with nitrogen of the air at very low temperatures
doneclear
C)
a change in the partial pressure of oxygen in the air
doneclear
D)
an interaction with water vapour contained in the humid air
question_answer45) The\[E_{{{M}^{3+}}/{{M}^{2+}}}^{o}\]values for\[Cr,Mn,Fe\]and\[Co\]are\[-0.41+1.57.+0.77\]and\[+1.97\text{ }V\]respectively. For which one of these metals the change in oxidation state from +2 to +3 is easiest?
question_answer46) Excess of\[KI\]reacts with\[CuS{{O}_{4}}\]solution and then\[N{{a}_{2}}{{S}_{2}}{{O}_{3}}\]solution is added to it. Which of the statements is incorrect for this reaction?
question_answer47) Among the properties (A) reducing (B) oxidizing (C) completing, the set of properties shown by\[C{{N}^{-}}\]ion towards metal species is
question_answer53) The correct order of magnetic moments (spin only values in BM) among the following is (At. nos.\[Mn=25,\text{ }Fe=26,\text{ }Co=27\])
question_answer54) Consider the following nuclear reactions \[_{92}^{238}M\to _{y}^{x}N+2_{2}^{4}He;_{y}^{x}N\to _{B}^{A}L+2{{\beta }^{+}}\] The number of neutrons in the element L is
question_answer55) The half-life of a radioisotope is four hours. If the initial mass of the isotope was 200 g, the mass remaining after 24 h undecayed is
question_answer57) The ammonia evolved from the treatment of 0.30 g of an organic compound for the estimation of nitrogen was passed in 100 mL of 0.1 M sulphuric acid. The excess of acid required 20 mL of 0.5 M sodium hydroxide solution for complete neutralization. The organic compound is
question_answer64) Consider the acidity of the carboxylic acids (i) \[PhCOOH\] (ii) \[o-N{{O}_{2}}{{C}_{6}}{{H}_{4}}COOH\] (iii) \[p-N{{O}_{2}}{{C}_{6}}{{H}_{4}}COOH\] (iv) \[m-N{{O}_{2}}{{C}_{6}}{{H}_{4}}COOH\] Which of the following order is correct?
question_answer74) Insulin production and its action in human body are responsible for the level of diabetes. This compound belongs to which of the following categories?