The de Broglie wavelength of an electron in the $$4^{th}$$ Bohr orbit is:
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The de Broglie wavelength of an electron in the $$4^{th}$$ Bohr orbit is:
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B has a smaller first ionization enthalpy than Be. Consider the following statement:
(I) it is easier to remove 2p electron than 2s electron
(II) 2p electron of B is more shielded from the nucleus by the inner core of electrons than the 2s electrons of Be
(III) 2s electron has more penetration power than 2p electron
(IV) atomic radius of B is more than Be
(atomic number B : 5, Be = 4)
The correct statements are:
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The acidic, basic and amphoteric oxides, respectively, are:
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If the magnetic moment of a di-oxygen species is 1.73 B.M., it may be:
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If enthalpy of atomization for $$Br_2(l)$$ is $$x$$ kJ/mol and bond enthalpy for $$Br_2$$ is $$y$$ kJ/mol, the relation between them:
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The $$K_{sp}$$ for the following dissociation is $$1.6 \times 10^{-5}$$
$$PbCl_{2(s)} \rightleftharpoons Pb^{2+}_{(aq)} + 2Cl^{-}_{(aq)}$$
Which of the following choices is correct for a mixture of 300 mL 0.134 M $$Pb(NO_3)_2$$ and 100 mL 0.4 M NaCl?
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The compound that cannot act both as oxidizing and reducing agent is:
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'X' melts at low temperature and is a bad conductor of electricity in both liquid and solid state. X is:
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The increasing order of basicity for the following intermediates is (from weak to strong):
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The correct order of heat of combustion for following alkadienes is:
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The major product (Y) in the following reactions is:
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For the following reactions:
$$A \xrightarrow{700K} Product$$
$$A \xrightarrow[catalyst]{500K} Product$$
It was found that the $$E_a$$ is decreased by 30 KJ/mol in the presence of catalyst. If the rate remains unchanged, the activation energy for catalysed reaction is (Assume pre-exponential factor is same):
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According to the following diagram, A reduces $$BO_2$$ when the temperature is:
The electronic configurations of bivalent europium and trivalent cerium are:
(atomic number: Xe = 54, Ce = 58, Eu = 63)
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Complex X of composition $$Cr(H_2O)_6Cl_n$$ has a spin only magnetic moment of 3.83 B.M. It reacts with $$AgNO_3$$ and shows geometrical isomerism. The IUPAC nomenclature of X is:
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$$[Pd(F)(Cl)(Br)(I)]^{2-}$$ has $$n$$ number of geometrical isomers. Then, the spin-only magnetic moment and crystal field stabilization energy [CFSE] of $$[Fe(CN)_6]^{n-6}$$, respectively, are:
[Note: Ignore the pairing energy]
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Which of these will produce the highest yield Friedel Crafts reaction?
Identify (A) in the following reaction sequence:
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The major product Z obtained in the following reaction scheme is:
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A chemist has 4 samples of artificial sweetener A, B, C and D. To identify these samples, he performed certain experiments and noted the following observations:
(i) A and D both form blue-violet colour with ninhydrin.
(ii) Lassaigne extract of C gives positive $$AgNO_3$$ test and negative $$Fe_4[Fe(CN)_6]_3$$ test.
(iii) Lassaigne extract of B and D gives positive sodium nitroprusside test.
Based on these observations which option is correct?
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The molarity of $$HNO_3$$ in a sample which has density 1.4 g/mL and mass percentage of 63% is ___________.
(Molecular Weight of $$HNO_3 = 63$$)
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The hardness of a water sample containing $$10^{-3}$$ M $$MgSO_4$$ expressed as $$CaCO_3$$ equivalents (in ppm) is ___________.
(molar mass of $$MgSO_4$$ is 120.37 g/mol)
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How much amount of NaCl should be added to 600 g of water $$(\rho = 1.00 \; g/mL)$$ to decrease the freezing point of water to $$-0.2$$ °C? ___________. (The freezing point depression constant for water $$= 2$$ K $$kg \; mol^{-1}$$)
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108 g of silver (molar mass 108 $$gmol^{-1}$$) is deposited at cathode from $$AgNO_3(aq)$$ solution by a certain quantity of electricity. The volume (in L) of oxygen gas produced at 273 K and 1 bar pressure from water by the same quantity of electricity is ___________.
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The mass percentage of nitrogen in histamine is ___________.
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