In the standard CSIR NET question on basicity of anions (typically involving cyclopentadienyl anion, indenyl anion, and fluorenyl anion or similar conjugated/aromatic carbanions): the more stable the conjugate carbanion (due to resonance or aromaticity), the weaker its basicity. Specifically, cyclopentadienyl anion is less resonance-delocalized across multiple rings, hence the order of basicity decreases with increasing aromatic resonance stabilization, giving $\text{II} > \text{III} > \text{I}$.
Q22mcq
The major product formed in the reaction of 2, 5-hexanedione with $\text{P}_2\text{O}_5$ is
Step-by-Step AI Explanation
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The reaction of 2,5-hexanedione (a 1,4-diketone) with a dehydrating agent like $\text{P}_2\text{O}_5$ is the classical Paal-Knorr furan synthesis, yielding 2,5-dimethylfuran as the major product.
Q23mcq
The absolute configuration of the two stereogenic (chiral) centres in the following molecule is
a.
5R, 6R
b.
5R, 6S
Correct Answer
c.
5S 6R
d.
5S, 6S
Step-by-Step AI Explanation
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By applying the Cahn-Ingold-Prelog (CIP) priority rules to the chiral carbons at positions 5 and 6 of the bicyclic/ring skeleton, the priorities of the substituents establish that C5 has the $(R)$ configuration and C6 has the $(S)$ configuration, giving (5R, 6S).
Q24mcq
The correct statement about the following molecule is
a.
Molecular is chiral and possesses a chiral plane
b.
Molecule is chiral and possesses a chiral axis.
Correct Answer
c.
Molecule is achiral as it possesses a plane of symmetry.
d.
Molecule is achiral as it possesses a centre of symmetry.
Step-by-Step AI Explanation
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Molecules such as sterically hindered biaryls, alkylidene cyclohexanes, or spiranes/allenes exhibit axial chirality. The molecule possesses a chiral axis (stereogenic axis) and lacks a plane or center of symmetry, making it chiral.
Q25mcq
Consider the following statements about cis- and trans-decalins
(A) cis-isomer is more stable than trans-isomer
(B) trans-isomer is more stable than cis-isomer
(C) trans-isomer undergoes ring-flip
(D) cis-isomer undergoes ring-flip
The correct statements among the above are
a.
B and D
Correct Answer
b.
A and C
c.
A and D
d.
B and C
Step-by-Step AI Explanation
Verified Method
For decalins: trans-decalin has two fused chair cyclohexanes locked in diequatorial positions, so it is conformationally rigid and cannot undergo ring-flip. In contrast, cis-decalin is flexible and rapidly undergoes ring-flipping. Furthermore, trans-decalin has zero butane-gauche interactions between the two rings whereas cis-decalin has three, making trans-decalin more stable than cis-decalin by about $2.7\text{ kcal/mol}$. Thus, statements (B) and (D) are correct.
Q26mcq
In bis(dimethylglyoximato)nickel(II), the number of $\text{Ni}-\text{N}$, $\text{Ni}-\text{O}$ and intramolecular hydrogen bond(s), respectively are
a.
4, 0 and 2
Correct Answer
b.
2, 2 and 2
c.
2, 2 and 0
d.
4, 0 and 1
Step-by-Step AI Explanation
Verified Method
In the square-planar bis(dimethylglyoximato)nickel(II) complex, $\text{[Ni(dmgH)}_2\text{]}$, nickel is coordinated to four nitrogen atoms (forming four $\text{Ni}-\text{N}$ bonds and zero $\text{Ni}-\text{O}$ bonds), and the structure is stabilized by two intramolecular $\text{O}-\text{H}\cdots\text{O}$ hydrogen bonds. Therefore, the numbers are 4, 0, and 2, respectively.
Q27mcq
Among the following species, (A) $\text{Ni(II)}$ as dimethylglyoximate, (B) $\text{Al(III)}$ as oximate, (C) $\text{Ag(I)}$ as chloride, those that precipitate with the urea hydrolysis method are
a.
A, B and C
b.
A and B
Correct Answer
c.
A and C
d.
B and C
Step-by-Step AI Explanation
Verified Method
Urea hydrolysis generates ammonia slowly in solution (homogeneous precipitation via pH increase): $\text{(NH}_2\text{)}_2\text{CO} + \text{H}_2\text{O} \to 2\text{NH}_3 + \text{CO}_2$. Precipitation of nickel as dimethylglyoximate and aluminum as oximate (8-hydroxyquinolate) are carried out by gradually raising the pH using urea hydrolysis to achieve controlled, crystalline precipitation. Silver chloride, on the other hand, is precipitated by generating chloride ions (e.g., using allyl chloride or 2-chloroethanol), not by pH adjustment via urea hydrolysis. Thus, only A and B precipitate via the urea hydrolysis method.
Q28mcq
If an enzyme fixes $\text{N}_2$ in plants by evolving $\text{H}_2$, the number of electrons and protons associated with that, respectively are
a.
6 and 6
b.
8 and 8
Correct Answer
c.
6 and 8
d.
8 and 6
Step-by-Step AI Explanation
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The biological nitrogen fixation catalyzed by the enzyme nitrogenase follows the stoichiometry: $\text{N}_2 + 8\text{H}^+ + 8\text{e}^- + 16\text{MgATP} \to 2\text{NH}_3 + \text{H}_2 + 16\text{MgADP} + 16\text{P}_i$. Thus, the reduction of one molecule of $\text{N}_2$ with obligate evolution of one molecule of $\text{H}_2$ requires 8 electrons and 8 protons.
Q29mcq
The particles postulated to always accompany the positron emission among
(A) neutrino,
(B) anti-neutrino,
(C) electron,
are
a.
A, B and C
b.
A and B
c.
A and C
Correct Answer
d.
B and C
Step-by-Step AI Explanation
Verified Method
In $\beta^+$ decay (positron emission), a proton converts into a neutron inside the nucleus, emitting a positron and an electron neutrino:
$$p \to n + e^+ + \nu_e$$
Simultaneously, the atom must lose an orbital electron to maintain electrical neutrality, as the atomic number decreases by 1 ($Z \to Z - 1$). Thus, along with the neutrino (A), an orbital electron (C) is lost. Therefore, both the neutrino and the electron (A and C) accompany the positron emission process.
Q30mcq
Toxicity of cadmium and mercury in the body is being reversed by proteins, mainly using the amino acid residue,
a.
Glycine
b.
Leucine
c.
Lysine
d.
Cysteine
Correct Answer
Step-by-Step AI Explanation
Verified Method
Cadmium ($ ext{Cd}^{2+}$) and mercury ($ ext{Hg}^{2+}$) are soft Lewis acids with a very high affinity for soft Lewis bases such as thiols/sulfhydryl groups ($- ext{SH}$). Metallothioneins are cysteine-rich proteins that sequester these toxic heavy metal ions in the body through coordination with cysteine residues.
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$\text{NiBr}_2$ reacts with $(\text{Et})(\text{Ph}_2)\text{P}$ at $-78^\circ\text{C}$ in $\text{CS}_2$ to give red compound 'A', which upon standing at room temperature turns green to give compound, 'B' of the same formula. The measured magnetic moments of 'A' and 'B' are $0.0$ and $3.2\text{ BM}$, respectively. The geometries of 'A' and 'B' are
a.
square planar and tetrahedral
b.
tetrahedral and square planar
c.
square planar and octahedral
d.
tetrahedral and octahedral
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The ligand(s) that is (are) fluxional in $[(\eta^5-\text{C}_5\text{H}_5)(\eta^1-\text{C}_5\text{H}_5)\text{Fe}(\text{CO})_2]$ in the temperature range 221–298K, is (are)
a.
$\eta^5-\text{C}_5\text{H}_5$
b.
$\eta^1-\text{C}_5\text{H}_5$
c.
$\eta^5-\text{C}_5\text{H}_5$ and $\text{CO}$
d.
$\eta^1-\text{C}_5\text{H}_5$ and $\text{CO}$
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The oxidation state of $\text{Ni}$ and the number of metal-metal bonds in $[\text{Ni}_2(\text{CO})_6]^{2-}$ that are consistent with the 18 electron rule are
a.
$\text{Ni}(-\text{II})$, 1 bond
b.
$\text{Ni}(\text{IV})$, 2 bonds
c.
$\text{Ni}(-\text{I})$, 1 bond
d.
$\text{Ni}(\text{IV})$, 3 bonds
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The $\text{pK}_\text{a}$ values of the following salt of aspartic acid are indicated below. The predominant species that would exist at $\text{pH} = 5$ is
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The commutator of the kinetic energy operator, $\hat{\mathrm{T}}_{\mathrm{x}}$ and the momentum operator, $\hat{\mathrm{p}}_{\mathrm{x}}$ for the one-dimensional case is
a.
$i\hbar$
b.
$i\hbar\dfrac{\mathrm{d}}{\mathrm{dx}}$
c.
$0$
d.
$i\hbar x$
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For a first order reaction $\mathrm{A} \rightarrow \text{products}$, the plot of $\ln\dfrac{[\mathrm{A}]_{\mathrm{t}}}{[\mathrm{A}]_0}$ vs time, where $[\mathrm{A}]_0$ and $[\mathrm{A}]_{\mathrm{t}}$ refer to concentration at time $t = 0$ and $t$ respectively, is
a.
a straight line with a positive slope passing through origin
b.
a straight line with a negative slope passing through origin.
c.
an exponential curve asymptotic to the time axis
d.
a curve asymptotic to the $\ln\left(\dfrac{[\mathrm{A}]_{\mathrm{t}}}{[\mathrm{A}]_0}\right)$ axis.
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Examine the following first order consecutive reactions. The rate constant (in $\text{s}^{-1}$ units) for each step is given above the arrow mark
(A) $\text{P} \xrightarrow{10^5} \text{Q} \xrightarrow{10^8} \text{R}$
(B) $\text{P} \xrightarrow{10^5} \text{Q} \xrightarrow{10^3} \text{R}$
(C) $\text{P} \xrightarrow{10^7} \text{Q} \xrightarrow{10^7} \text{R}$
(D) $\text{P} \xrightarrow{10^2} \text{Q} \xrightarrow{10^6} \text{R}$
Steady-state approximation can be applied to
a.
A only
b.
C only
c.
B and C only
d.
A and D only
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An aqueous solution of an optically pure compound of concentration $100\text{ mg}$ in $1\text{ mL}$ of water and measured in a quartz tube of $5\text{ cm}$ length was found to be $-3^\circ$. The specific rotation is
a.
$-30^\circ$
b.
$-60^\circ$
c.
$-6^\circ$
d.
$+6^\circ$
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Two phases ($\alpha$ and $\beta$) of a species are in equilibrium. The correct relations observed among the variables, $\text{T}$, $\text{p}$ and $\mu$ are
Consider the statements about the following structures X and Y
(A) X and Y are resonance structures
(B) X and Y are tautomers
(C) Y is more basic than X
(D) X is more basic than Y
The correct statement(s) among the above is/are
a.
A and C
b.
C
c.
B and D
d.
B and C
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Reaction of $[\text{Ru}(\text{NH}_3)_5(\text{isonicotinamide})]^{3+}$ with $[\text{Cr}(\text{H}_2\text{O})_6]^{2+}$ occurs by inner sphere mechanism and rate of th reaction is determined by dissociation of the successor complex. It is due to the
a.
Inert ruthenium birdged to inert chromium centre
b.
Inert ruthenium bridged to labile chromium centre
c.
Labile ruthenium bridged to inert chromium centre
d.
Labile ruthenium bridged to labile chromium centre
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Consider the second order rate constants for the following outer-sphere electron transfer reactions:
$$[\text{Fe}(\text{H}_2\text{O})_6]^{3+} / [\text{Fe}(\text{H}_2\text{O})_6]^{2+} \quad 4.0\text{ M}^{-1}\text{ sec}^{-1}$$
$$[\text{Fe}(\text{phen})_3]^{3+} / [\text{Fe}(\text{phen})_3]^{2+} \quad 3.0 \times 10^7\text{ M}^{-1}$$
($\text{phen} = 1, 10\text{-phenanthroline}$)
The enhanced rate constant for the second reaction is due to the fact that
a.
The 'phen' is a $\pi$-acceptor ligand that allows mixing of electron donor and acceptor orbitals that enhances the rate of electron transfer
b.
The 'phen' is a $\pi$-donor ligand that enhances the rate of electron transfer
c.
The 'phen' forms charge transfer complex with iron and facilitates the eletron transfer
d.
The 'phen' forms kinetically labile complex with iron and facilitates the electron transfer.
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The compound $[\text{Re}_2(\text{Me}_2\text{PPh})_4\text{Cl}_4]$ ($\text{M}$) having a configuration of $\sigma^2\pi^4\delta^2\delta^{*2}$ can be oxidized to $\text{M}^+$ and $\text{M}^{2+}$. The formal metal-metal order in $\text{M}$, $\text{M}^+$ and $\text{M}^{2+}$ respectively, are
a.
3.0, 3.5 and 4.0
b.
3.5, 4.0 and 3.0
c.
4.0, 3.5 and 3.0
d.
3.0, 4.0 and 3.5
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In low chloride ion concentration, the anticancer drug cis-platin hydrolyses to give a diaqua complex and this binds to DNA via adjacent guanine
The coordinating atom of guanine to $\text{Pt(II)}$ is
a.
N1
b.
N3
c.
N7
d.
N9
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The low temperature ($-98^\circ\text{C}$) $^{19}\text{F}$ NMR spectrum of $\text{SF}_4$ shows doublet of triplets. It is consistent with the point group symmetry.
a.
$\text{C}_{3\text{v}}$
b.
$\text{C}_{4\text{v}}$
c.
$\text{T}_\text{d}$
d.
$\text{C}_{2\text{v}}$
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In its electronic spectrum, $[\mathrm{V}(\mathrm{H}_2\mathrm{O})_6]^{3+}$ exhibits two absorption bands, one at $17,800\ (\nu_1)$ and the second at $25,700\ (\nu_2)\text{ cm}^{-1}$. The correct assignment of these bands, respectively, is
$^1\mathrm{H}\text{ NMR}$ spectrum of $[\eta^5-\mathrm{C}_5\mathrm{H}_5\mathrm{Rh}(\mathrm{C}_2\mathrm{H}_4)_2]$ at $-20^\circ\mathrm{C}$ shows a typical $\mathrm{AA'XX'}$ pattern in the olefinic region. On increasing the temperature to $\sim 70^\circ\mathrm{C}$, the separate lines collapse into a single line which is due to
a.
free rotation of the ethylene ligand about the metal-olefin bond
b.
interamolecular exchange between the ethylene ligands
c.
intermolecular exchange between the ethylene ligands
d.
change in hapticity of the cyclopentadienyl ligand
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The nuclides among the following, capable of undergoing fission by thermal neutrons, are
(A) $^{233}\mathrm{U}$
(B) $^{235}\mathrm{U}$
(C) $^{239}\mathrm{Pu}$
(D) $^{232}\mathrm{Th}$
a.
A, B and D
b.
A, C and D
c.
B, C and D
d.
A, B and C
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The correct statements for hollow cathode lamp (HCL) from the following are
(A) HCL is suitable for atomic absorption spectroscopy (AAS)
(B) lines emitted from HCL are very narrow
(C) the hardening of lamp makes it unsuitbale for AAS
(D) transition elements used in lamps have short life
a.
A, B and C
b.
B, C and D
c.
C, D and A
d.
D, A and B
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Reaction of nitrosyl tetrafluoroborate to Vaska's complex gives complex A with $\angle\mathrm{M}-\mathrm{N}-\mathrm{O} = 124^\circ$. The complex A and its N-O stretching frequency are, respectively
A $1 : 2$ mixture of $\text{Me}_2\text{NCH}_2\text{CH}_2\text{CH}_2\text{PPh}_2$ and $\text{KSCN}$ with $\text{K}_2[\text{PdCl}_4]$ gives a square planar complex A. Identify the correct pairs of donor atoms trans to each other in complex A from the following combinations.
a.
P, N
b.
N, S
c.
P, S
d.
N, N
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For a low energy nuclear reaction, $^{24}\text{Mg}(\text{d}, \alpha)^{22}\text{Na}$, the correct statements from the following are
(A) Kinetic energy of d particle is not fully available for exciting $^{24}\text{Mg}$.
(B) Total number of protons and neutrons is conserved
(C) Q value of nuclear reaction is much higher in magnitude relative to heat of chemical reaction
(D) Threshold energy is $\le \text{Q}$ value.
a.
A, B and C
b.
A, B and D
c.
B, C and D
d.
A, C and D
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The biosynthesis of isopentenyl pyrophosphate from acetyl CoA involves:
A. Four molecules of acetyl CoA
B. Three molecules of ATP
C. Two molecules of NADPH
D. Two molecules of lipoic acid
The correct options among these are
a.
A, B and D
b.
A and B
c.
B and C
d.
A, C and D
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Anthranilic acid, on treament with iso-amyl nitrite furnishes a product which displays a strong peak at 76 (m/e) in its mass spectrum. The strucrture of the product is
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The organoborane $\text{X}$, when reacted with $\text{Et}_2\text{Zn}$ followed by p-iodotoluene in the presence of catalytic amount of $\text{Pd(PPh}_3)_4$ furnishes a tri-substituted alkene. The intermediate and the product of the reaction, respectively, are
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Using Boltzmann distribution, the probability of an oscillator occupying the first three levels ($n = 0$, $1$ and $2$) is found to be $p_0 = 0.633$, $p_1 = 0.233$ and $p_2 = 0.086$.
The probability of finding an oscillator in energy levels in $n \ge 3$ is
a.
0.032
b.
0.048
c.
0.952
d.
1.000
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The number of phases, components and degrees of freedom, when $\text{Ar}$ is added to an equilibrium mixture of $\text{NO}$, $\text{O}_2$ and $\text{NO}_2$ in gas phase are, respectively,
a.
1, 3, 5
b.
1, 4, 5
c.
1, 3, 4
d.
1, 4, 4
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A particle in a one dimensional harmonic oscillator in x-direction is perturbed by a potential $\lambda x$ ($\lambda$ is a number). The first-order correction to the energy of the ground state
a.
is zero
b.
is negative
c.
is positive
d.
may be negative or positive but NOT zero.
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The mass spectrum of the product A, formed in the following reaction, exhibits M, M+2, M + 4 peaks in the ratio of about $1 : 2 : 1$. The reagent HX and the product A are
a.
$\text{HX} = \text{HF}$ and $\text{A} =$ 1-(4-bromophenyl)-1-fluoropropane
b.
$\text{HX} = \text{HCl}$ and $\text{A} =$ 1-(4-bromophenyl)-1-chloropropane
c.
$\text{HX} = \text{HBr}$ and $\text{A} =$ 1-(4-bromophenyl)-1-bromopropane
d.
$\text{HX} = \text{HBr}$ and $\text{A} =$ 1-(4-bromophenyl)-2-bromopropane
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Match the following natural products in column A with their structural features in column B
\begin{tabular}{ll}
\textbf{Column A} & \textbf{Column B} \\
(I) Colchicine & (A) Tetrahydrooxepine \\
(II) Strychnine & (B) Phenanthrene \\
(III) Quinine & (C) Tropolone \\
(IV) Ephedrine & (D) Phenylethylamine \\
& (E) Quinoline \\
& (F) Benzofuran
\end{tabular}
Identify the correct match from the following
a.
I-C, II-A, III-E, IV-D
b.
I-F, II-A, III-B, IV-E
c.
I-A, II-D, III-F, IV-D
d.
I-C, II-A, III-E, IV-F
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A particle in a one-dimensional box (potential zero between to a and infinite outside) has the ground state energy $E_0 = \frac{0.125h^2}{\text{ma}^2}$. The expectation value of the above Hamiltonian with $\psi(x) = x(x-a)$ yields an energy $E_1$. Using a linear combination of two even functions $x(x-a)$ and $x^2(x-a)^2$, we obtain variational mainimum to the ground state energy as $E_2$. Which of the following relations holds for $E_0$, $E_1$ and $E_2$?
a.
$E_0 < E_1 < E_2$
b.
$E_0 < E_2 < E_1$
c.
$E_1 < E_0 < E_2$
d.
$E_2 < E_0 < E_1$
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The dissociation constant of a weak acid $\text{HX}$ at a given temperature is $2.5 \times 10^{-5}$. The pH of $0.01\text{ M}$ $\text{NaX}$ at this temperature is
a.
$7.3$
b.
$7.7$
c.
$8.3$
d.
$8.7$
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The ground state energy of hydrogen atom is $-13.598\text{ eV}$. The expectation values of kinetic energy, $\langle T \rangle$ and potential energy, $\langle V \rangle$, in units of $\text{eV}$, are
a.
$\langle T \rangle = 13.598, \langle V \rangle = -27.196$
b.
$\langle T \rangle = -27.196, \langle V \rangle = 13.598$
c.
$\langle T \rangle = -6.799, \langle V \rangle = -6.799$
d.
$\langle T \rangle = 6.799, \langle V \rangle = -20.397$
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If $\psi = 0.8\,\varphi_A + 0.4\,\varphi_B$ is a normalized molecular orbital of a diaotmic molecule $\text{AB}$, constructed from $\varphi_A$ and $\varphi_B$ which are also normalized, the overlap between $\varphi_A$ and $\varphi_B$ is
a.
$0.11$
b.
$0.31$
c.
$0.51$
d.
$0.71$
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In a bomb calorimeter, the combustion of $0.5\text{ g}$ of compound A (molar mass = $50\text{ g mol}^{-1}$) increased the temperature by $4\text{K}$. If the heat capacity of the calorimeter along with that of the material is $2.5\text{ kJ K}^{-1}$, the molar internal energy of combustion, in $\text{kJ}$, is
a.
$1000$
b.
$-1000$
c.
$20$
d.
$-20$
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The translational, rotational and vibrational partition functions for a molecule are
$f_{\text{translation}} \simeq 10^{10}\text{ m}^{-1}$, $f_{\text{rotation}} \simeq f_{\text{vibration}} \simeq 1$, $(k_B\text{T} / h) \simeq 10^{13}$ at room temperature, $N_A \simeq 6 \times 10^{23}$
Using the approximate data given above, the frequency factor (A) for a reaction of the type:
atom + diatomic molecule $\rightarrow$ non-linear transtion state $\rightarrow$ product, according to the conventional transition state theory is
a.
$2 \times 10^3$
b.
$6 \times 10^7$
c.
$2 \times 10^{12}$
d.
$6 \times 10^{13}$
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A compound $\text{A}_\text{x}\text{B}_\text{y}$ has a cubic structure with A atoms occupying all corners of the cube as well as all the face centre positions. The B atoms occupy four tetrahedral voids. The values of x and y respectively, are
a.
4, 4
b.
4, 8
c.
8, 4
d.
4, 2
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The $\text{C}=\text{O}$ bond length is $120\text{ pm}$ in $\text{CO}_2$. The moment of inertia of $\text{CO}_2$ would be close to (masses of C and O are $1.9\times 10^{-27}\text{ kg}$ and $2.5\times 10^{-27}\text{ kg}$, respectively)
a.
$1.8\times 10^{-45}\text{ kgm}^2$
b.
$3.6\times 10^{-45}\text{ kgm}^2$
c.
$5.4\times 10^{-45}\text{ kgm}^2$
d.
$7.2\times 10^{-45}\text{ kgm}^2$
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The fluorescence lifetime of a molecule in a solution is $5\times 10^{-9}\text{ s}$. The sum of all of the non-radiative rate constants $(\Sigma\text{k}_{\text{nr}})$ for the decay of excited state is $1.2\times 10^8\text{ s}^{-1}$. The fluorescence quantum yield of the molecule is
a.
0.1
b.
0.2
c.
0.4
d.
0.6
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Solutions of three electrolytes have the same ionic strength and different dielectric constants as 4, 25 and 81. The corresponding relative magnitude of Debye-Hückel screening, lengths of the three solutions are
a.
4, 25 and 81
b.
2, 5 and 9
c.
1/2, 1/5 and 1/9
d.
1, 1 and 1
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For the non-dissociative Langmuir type adsorption of a gas on a solid surface at a particular temperature, the fraction of surface coverage is 0.6 at 30 bar. The Langmuir isotherm constant (in $\text{bar}^{-1}$ units) at this temperature is
a.
0.05
b.
0.20
c.
2.0
d.
5.0
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For a set of 10 observed data points, the mean is 8 and the variance is 0.04. The 'standard deviation' and the 'coefficient of variation' of the data are, respectively
a.
0.005, 0.1%
b.
0.02, 0.2%
c.
0.20, 2.5%
d.
0.32, 1.0%
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In the Lineweaver-Burk plot of $\text{(initial rate)}^{-1}$ vs. $\text{(initial substrate concentration)}^{-1}$ for an enzyme catalyzed reaction following Michaelis-Menten mechanism, the y-intercept is $5000\text{ M}^{-1}\text{ s}$. If the initial enzyme concentration is $1\times 10^{-9}\text{ M}$, the turnover number is
a.
$2.5\times 10^3$
b.
$1.0\times 10^4$
c.
$2.5\times 10^4$
d.
$2.0\times 10^5$
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Given;
A. $\text{Fe(OH)}_2(\text{s}) + 2\text{e}^- \rightarrow \text{Fe(s)} + 2\text{OH}^-(\text{aq}); \text{E}^0 = -0.877\text{ V}$
B. $\text{Al}^{3+}(\text{aq}) + 3\text{e}^- \rightarrow \text{Al(s)}; \text{E}^0 = -1.66\text{ V}$
C. $\text{AgBr(aq)} + \text{e}^- \rightarrow \text{Ag(s)} + \text{Br}^-(\text{aq}); \text{E}^0 = 0.071\text{ V}$
The overall reaction for the cells in the direction of spontaneous change would be
a.
Cell with A and B : Fe reduced
Cell with A and C : Fe reduced
b.
Cell with A and B : Fe reduced
Cell with A and C : Fe oxidized
c.
Cell with A and B : Fe oxidized
Cell with A and C : Fe oxidized
d.
Cell with A and B : Fe oxidized
Cell with A and C : Fe reduced
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