Grass-G/jee-main-questions huggingface dataset:
Subject: Chemistry — Organic Chemistry — Hydrocarbon
Difficulty: Moderate

Question: Which of the following compounds on hydrolysis gives propyne ?

1) CaC_2
2) Mg_2C_3
3) Al_4C_3
4) Cu_2Cl_2

Correct option: 1

Solution:
Subject: Chemistry — Organic Chemistry — HALOALKANES & HALOARENES
Difficulty: Moderate

Question: C6 H5Cl prepared by aniline with

1) HCl
2) Cu_2Cl_2
3) Cl_2 in presence of anhydrous Alcl_3
4) HNO_2 and then heated with Cu_2 Cl_2

Correct option: 4

Solution:
Subject: Chemistry — Physical Chemistry — Ionic equilibrium
Difficulty: Moderate

Question: On mixing equal volumes of 0.1 M AgNO3 & 0.8 M KCN solutions,
what of original Ag+ is in the form of free Ag+ ions ? Given: Kd of
[Ag(CN)2]- = 10-18. Report your answer after multiplying it by 4.5 ×
1016. (Assume no hydrolysis of any ion)


Answer: 50

Solution:
$10^{- 18} = \frac{\left\lbrack {Ag}^{+} \right\rbrack_{free}(0.3)^{2}}{(0.05)} \Rightarrow \left\lbrack {Ag}^{+} \right\rbrack_{free} = \frac{5}{9} \times 10^{- 18}M$
$\%\ of\ {Ag}^{+}\left( {Ag}^{+}\% \right) = \frac{\frac{5}{9} \times 10^{- 18}}{0.05} \times 100 \times 4.5 \times 10^{16} = 50\%$
Subject: Chemistry — Inorganic Chemistry — Qualitative
Difficulty: Moderate

Question: A Precipitate of PbSO4 is soluble in

1) ammonium acetate (6M)
2) dilute HCl
3) dilute $H_{2}{SO}_{4}$
4) none of these

Correct option: 1

Solution:
${PbSO}_{4} + 2{CH}_{3}{COONH}_{4} \longrightarrow \left( {NH}_{4} \right)_{2}{SO}_{4} + \left( {NH}_{4} \right)_{2}\left\lbrack Pb\left( {CH}_{3}COO \right)_{4} \right\rbrack$
Subject: Chemistry — Organic Chemistry — Organic Chemistry
Difficulty: Tough

Question: Number of [IMAGE] bonds in


Answer: 15

Solution:
Subject: Chemistry — Physical Chemistry — Chemical Kinetics & Radioactivity
Difficulty: Tough

Question: A radioactive element gets spilled over the floor of a room. Its
half-life period is 30days. If the initial activity is ten times the
permissible value, after how many days will it be safe to enter the
room


Answer: 100

Solution:
Let A be the activity for safe working
Given $A_{0} = 10A$ $Ao \times No\ and\ A \times N$
$t = \frac{2.303}{\lambda}\log\frac{N_{0}}{N} = \frac{2.303}{\lambda}\log\frac{A_{0}}{A}$
$= \frac{\frac{2.303}{0.693}}{30}\log\frac{10A}{A} = \frac{2.303 \times 30}{0.693}\log 10 = \frac{2.303 \times 30}{0.693} = 99.69days \approx 100\ days\ $
Subject: Chemistry — Organic Chemistry — HALOALKANES & HALOARENES
Difficulty: Tough

Question: Salicylic acid can be prepared using Reimer-Tiemann's reaction
by treating phenol with

1) Methyl chloride in the presence of anhydrous aluminum chloride
2) Carbon dioxide under pressure in sodium hydroxide solution
3) Carbon tetrachloride and concentrated sodium hydroxide
4) Sodium nitrite and a few drops of concentrated sulphuric acid

Correct option: 3

Solution:
Subject: Chemistry — Inorganic Chemistry — Hydrogen And Its Compound
Difficulty: Easy

Question: The pH of $D_{2}O$ and $H_{2}O$ at 298 K is

1) 7.0, 7.0
2) 7.35, 7.0
3) 7.0, 6.85
4) 6.85, 7.35

Correct option: 2

Solution:
pH of heavy water slightly more than seven.
Subject: Chemistry — Inorganic Chemistry — Periodic properties
Difficulty: Moderate

Question: In which of the following arrangements the order is NOT
according to the property indicated against it

1) $Al^{3 +} < Mg^{2 +} < Na^{+} < F^{-}$: Increasing ionic size
2) $B < C < N < O$: Increasing first ionizationenthalpy
3) $I < Br < F < Cl$: Increasing electron gainenthalpy (with negative
sign)
4) $Li < Na < K < Rb$: Increasing metallic radius

Correct option: 2

Solution:
$B < C < N < O$; When we move from B to O in a periodic table
the first ionisation enthalpy increase due to the attraction of nucleus
towards the outer most of electron.
Subject: Chemistry — Stereoisomerism — Chiral carbon and Projection Formula
Difficulty: Easy

Question: Number of chiral carbon present in the following compound

1) 2
2) 3
3) 4
4) 5

Correct option: 2

Solution:
[IMAGE] has three chiral carbons.
Subject: Chemistry — Inorganic Chemistry — Coordination Compounds
Difficulty: Moderate

Question: Which of the following is an example of homoleptic complex?

1) $\left\lbrack Co\left( {NH}_{3} \right)_{6} \right\rbrack{Cl}_{3}$
2) $\left\lbrack Pt\left( {NH}_{3} \right)_{2} \right\rbrack{Cl}_{2}$
3) $\left\lbrack Co\left( {NH}_{3} \right)_{4} \right\rbrack{Cl}_{2}$
4) $\left\lbrack Co\left( {NH}_{3} \right)_{5}Cl \right\rbrack{Cl}_{3}$

Correct option: 1

Solution:
Those complexes that contain only one type of ligand that are
bound to the central metal atom are termed as Homoleptic complexes.
Therefore, the complex MnR^2 t is a homoleptic complex that has six
ammonia ligands bound to the central metal atom cobalt.
Subject: Chemistry — Physical Chemistry — Thermodynamics
Difficulty: Moderate

Question: The work done by a system is 8 joule. When 40 joule heat is
supplied to it? What is the increase in internal energy of system?

1) 25 J
2) 30 J
3) 32 J
4) 28 J

Correct option: 3

Solution:
q = 40 J [IMAGE]
Subject: Chemistry — Organic Chemistry — Aldehydes, Ketones & Carboxylic Acids
Difficulty: Moderate

Question: The reaction [IMAGE] is known as

2) Claisen condensation
3) Benzoin condensation

Correct option: 2

Solution:
Subject: Chemistry — Physical Chemistry — Ionic Equilibrium
Difficulty: Moderate

Question: What are and in a solution that
contains 0.03 M HA and 0.1 M HB. K_a for HA and HB are 3.0 × 10^-4
and 1.0 × 10^-10 respectively.

1) = 3 × 10^-3 M
2) = 3 × 10^-3 M
3) = 3.33 × 10^-9 M
4) All of these

Correct option: 4

Solution:
$\left\lbrack H^{+} \right\rbrack = \sqrt{K_{a1} \times C} = \sqrt{3 \times 10^{- 4} \times 3 \times 10^{- 2}} = 3 \times 10^{- 3}M$
Subject: Chemistry — Physical Chemistry — Thermodynamics
Difficulty: Easy

Question: Work done during isothermal expansion of one mole of an ideal
gas from 10 atm to 1 atm at [IMAGE] is (Gas constant = 2)


Correct option: 3

Solution:
Subject: Chemistry — Physical Chemistry — Mole Concept
Difficulty: Easy

Question: Which of the following compounds have sulphur atom in its maximum
oxidation state:
X = H_2SO_4; Y = H_2SO_5; Z = H_2S_2O_8

1) Z only
2) X only
3) Y only (4) X, Y and Z
 / ():
X = H_2SO_4; Y = H_2SO_5; Z = H_2S_2O_8

Answer: 4

Solution:
In all these three compounds
H_2SO_4; H_2SO_5; H_2S_2O_8 
maximum oxidation state.
 H_2SO_4; H_2SO_5; H_2S_2O_8 +6
Subject: Chemistry — Physical Chemistry — 
Difficulty: Moderate

Question: The vacant space in in the bcc unit cell is


Answer: 32

Solution:
In bcc structure 68 of the available volume is occupied by
spheres. Thus vacant space is 32.
Subject: Chemistry — IUPAC and Structural Isomerism — Position isomers
Difficulty: Moderate

Question: Total number of position isomers of trimethyl cyclohexane are

1) 5
2) 6
3) 7
4) 8

Correct option: 2

Solution:
Subject: Chemistry — Organic Chemistry — Aldehydes, Ketones & Carboxylic Acids
Difficulty: Easy

Question: The reagent that gives an orange coloured precipitate with
acetaldehyde

3) Iodine

Correct option: 1

Solution:
Brady's Reagent is 2,4-DNP i.e.
Subject: Chemistry — Physical Chemistry — Ideal Gases
Difficulty: Easy / Moderate/ Tough t

Question: The average velocity of gas molecules is 400 m/sec calculate its
r.m.s. velocity at the same temperature


Answer: 434

Solution:
$U_{av} = \sqrt{\frac{8RT}{\pi M}}$ and
$U_{rms} = \sqrt{\frac{3RT}{M}}$
$\therefore\frac{U_{av}}{U_{rms}} = \sqrt{\frac{8RT}{\pi M}} \times \sqrt{\frac{M}{3RT}} = \sqrt{\frac{8}{3\pi}} = 0.9216$
or $U_{av} = 0.9216 \times U_{rms}$
Given $U_{av} = 400m/s$
$U_{rms} = \frac{400}{0.9216} = 434.02m/s$
Subject: Chemistry — Physical Chemistry — Redox Reaction
Difficulty: Moderate

Question: Which is the best description of the behavior of bromine in the
reaction given below?
$H_{2}O + Br_{2} \rightarrow HOB^{2} + HBr$

1) Oxidized only
2) Reduced only
3) Proton acceptor only
4) Both oxidized and reduced

Correct option: 4

Solution:
[IMAGE] In the above reaction the oxidation number of Br_2 increases from
zero (in Br_2) to +1 (in HOBr) and decrease from zero (in
Br_2) to - 1 (in HBr). Thus Br_2 is oxidized as well as
reduced & hence it is a redox reaction.
Subject: Chemistry — Physical Chemistry — Mole Concept
Difficulty: Easy

Question: 39.4 kg of gold was recovered from a smuggler. The number of atoms
of gold recovered are:
 39.4 ?

1) 200
2) 1.2044 × 1025
3) 6.022 × 1025 (4) 1.2044 × 1026

Correct option: 4

Solution:
No. of atoms of gold recovered = Moles of gold
Subject: Chemistry — Chemical Kinetics — Integrated Rate law : Second Order & Pseudo first order
Difficulty: Moderate

Question: A graph between log [IMAGE] and log a (abscissa) a
being the initial concentration of A in the reaction. For reaction A→
Product, the rate law is

1) $\frac{- d\lbrack A\rbrack}{dt} = k$
2) $\frac{- d\lbrack A\rbrack}{dt} = k\lbrack A\rbrack$
3) $\frac{- d\lbrack A\rbrack}{dt} = k\lbrack A\rbrack^{2}$
4) $\frac{- d\lbrack A\rbrack}{dt} = k\lbrack A\rbrack^{3}$

Correct option: 3

Solution:
$t_{1/2} = {ka}^{(1 - n)}$, n being order k = Rate constant
$\log t_{1/2} = logk + (1 - n)\log a$
$1 - n = - 1$
$n = 2$
Subject: Chemistry — Physical Chemistry — Thermodynamics
Difficulty: Moderate

Question: If [IMAGE] then the possible heat of methane will be
___________________________ Kcal


Answer: 20

Solution:
[IMAGE] On multiplication of eq (ii) by 2 and then adding in eq (i)
[IMAGE] On subtracting eq. (iii) by following eq.
[IMAGE] We get,
Subject: Chemistry — Physical Chemistry — Ionic Equilibrium
Difficulty: Easy

Question: [IMAGE] of N_2H_4 is 4 × 10^-6. Then, what is
the acid dissociation constant of [IMAGE] and
[IMAGE] respectively ?

1) Data insufficient, 4 × 10^-6
2) Data insufficient, 2.5 × 10^-8
3) 2.5 × 10^-9, data insufficient
4) 2.5 × 10^-9, 4 × 10^-6

Correct option: 3

Solution:
$K_{a_{1}} = \frac{K_{w}}{K_{b_{1}}} = \frac{10^{- 14}}{4 \times 10^{- 6}} = 2.5 \times 10^{- 9}$
$K_{b_{2}}\ $data not given, so$\ K_{a_{2}}$ cannot be determined.
Subject: Chemistry — Physical Chemistry — 
Difficulty: Easy

Question: Coordination number for Cu is


Answer: 12

Solution:
Coordination number for Cu is
Subject: Chemistry — Organic Chemistry — Stability of Resonating Structures and different species
Difficulty: Moderate

Question: The correct stability order of the following resonanating
structures is

1) (IV) > (I) > (III) > (II)
2) (II) > (IV) > (I) > (III)
3) (III) > (II) > (IV) > (I)
4) (I) > (IV) > (III) > (II)

Correct option: 4

Solution:
I is the most stable resonating structure becasue it is
neutral.
IV has complete octet on each atoms, II and III both have incomplete
octet at 'C' atom bearing positive charge but in 'III' structure
negative charge is present on more electronegative atom i.e. oxygen.
Subject: Chemistry — Inorganic Chemistry — Coordination chemistry
Difficulty: Easy

Question: The formula of potassium dicyano bis (oxalato) nickelate (II) is

1) $K_{4}\lbrack Ni(CN)_{2}(Ox)_{2}\rbrack$
2) $K_{3}\lbrack Ni_{2}\lbrack Ni_{2}(CN)_{2}(Ox)_{2}\rbrack$
3) $K\lbrack Ni(CN)(Ox)_{2}\rbrack$
4) $K_{2}\lbrack Ni(CN)_{2}(Ox)_{2}\rbrack$

Correct option: 1

Solution:
Cyano has -1 charge and oxalato has -2 charge. For Ni(II) on
complex -4 charge should be present.
Subject: Chemistry — Inorganic Chemistry — p-block elements
Difficulty: Moderate

Question: Anhydrous AlCl_3  is obtained from

1) HCl and aluminium metal
2) Aluminium and chlorine gas
3) Hydrogen chloride gas and aluminium metal
4) None of the above

Correct option: 3

Solution:
2Al + 6HCl$\rightarrow$ 2AlC_3 + 3H_2
Subject: Chemistry — Inorganic Chemistry — Quatitative
Difficulty: Moderate

Question: An aqueous solution contains
${Hg}^{2 +},{Hg}_{2}^{2 +},{Pb}^{2 +}{Ag}^{+},{Bi}^{3 +}$ and
${Cd}^{2 +}$. Out of these, how many ions will produce white precipitate
with dilute HCl?


Answer: 3

Solution:
${Pb}^{2 +} + 2{Cl}^{-} \longrightarrow {PbCl}_{2} \downarrow (\ white\ );{Hg}_{2^{2 +}} + 2{Cl}^{-} \longrightarrow {Hg}_{2}{Cl}_{2} \downarrow (\ white\ )$
${Ag}^{+} + {Cl}^{-} \longrightarrow AgCl \downarrow \ (white)\ $
$K_{sp}$ of chlorides of ${Pb}^{2 +}$ and ${Hg}_{2}^{2 +}$is low as
compared to $K_{sp}$ of ${Hg}^{2 +}$ and ${Cd}^{2 +}$. Chloride ion
concentration provided by dilute HCl is just enough to exceed the
$K_{sp}$ of ${PbCl}_{2}$ and ${Hg}_{2}{Cl}_{2}$. Thus ${Pb}^{2 +}$ and
${Hg}_{2}^{2 +}$ are precipitated as their chlorides.
Subject: Chemistry — Inorganic Chemistry — Chemical Bonding
Difficulty: Moderate

Question: The set with correct order of acidity is

1) HClO < HClO2 < HClO3 < HClO4
(B) HClO4 < HClO3 < HClO2 < HClO
3) HClO < HClO4 < HClO3 < HClO2
4) HClO4 < HClO2 < HClO3 < HClO

Correct option: 1

Solution:
According to conjugate acid-base theory, that acid is more
acidic whose conjugate base is more stable. The order of the stability
of the conjugate bases of these acids is as follows:
ClO- < ClO2- < ClO3- < ClO4- on the basis of the charge
dispersion on the oxygen atoms (more charge dispersion on oxygen
atoms, more stable is the conjugate base). Also, for oxyacids of same
element, as oxidation state of element increases, acidic strength of
oxyacids increases.
Subject: Chemistry — Physical Chemistry — Chemical & Ionic Eqilibrium
Difficulty: Easy

Question: What is the pH value of [IMAGE] solution?


Answer: 11

Solution:
Subject: Chemistry — Inorganic Chemistry — P-block Halogen
Difficulty: Easy

Question: Which one of the following statements regarding helium is
incorrect ?

1) It is used to produce and sustain powerful superconducting magnets
2) It is used as a cryogenic agent for carrying out experiments at
low temperatures
3) It is used to fill gas balloons instead of hydrogen because it is
lighter and non- inflammable
4) It is used in gas-cooled nuclear reactors

Correct option: 3

Solution:
Helium is twice as heavy as hydrogen. But it is a
non-inflammable gas has 92 lifting power to that of hydrogen.
 ysfdu;g,d
 ftldh ngu 'kfDr gkbMªkstu
Subject: Chemistry — Inorganic Chemistry — P-block nitrogen
Difficulty: Easy

Question: Which of the following statements regarding sulphur is incorrect
?

1) S2 molecule is paramagnetic.
2) The vapour at 200ºC consists mostly of S8 rings.
3) At 600ºC the gas mainly consists of S2 molecules.
4) The oxidation state of sulphur is never less than +4 in its
compounds.
lYQj

Correct option: 4

Solution:
Sulphur exhibit + 2, + 4, + 6 oxidation states but + 4 and + 6
are more common.
Hindi. lYQj + 2, + 4, + 6 vkWDlhdj.k voLFkk,sa n'kkZrk
Subject: Chemistry — Physical Chemistry — Chemical Bonding
Difficulty: Tough

Question: Which of the following statements is not correct from the point of
view of molecular orbital theory

1) Be2 is not a stable molecule.
2) He2 is not stable, but [IMAGE] is expected to
exist.
3) Bond strength of N2 is maximum amongst the homonuclear diatomic
molecules.
(4) The order of energies of molecular orbitals in F2 molecule is:
[IMAGE]
4) For F2 molecule, [IMAGE] gy

Answer: 4

Solution:
(1) Be2: BO = 0 (zero) [IMAGE]  unstable
molecule.
(2) He2: BO = 0 (not stable), [IMAGE]: BO = 0.5
(expected to exist).
(3) N2: BO = 3, maximum bond order means maximum bond strength.
(4) For F2 molecule, [IMAGE] gy- (1) Be2: BO = 0 () [IMAGE] 
(2) He2: BO = 0 ( ), [IMAGE]: BO = 0.5
( ).
(3) N2: BO = 3,, 
(4) F2
Subject: Chemistry — Organic Chemistry — HALOALKANES & HALOARENES
Difficulty: Moderate

Question: Silver acetate[IMAGE]. The main product of this
reaction is

1) CH_3 - Br
2) CH_3 COI
3) CH_3 COOH
4) None of these

Correct option: 1

Solution:
Subject: Chemistry — Organic Chemistry — Organic Chemistry
Difficulty: Moderate

Question: Number of optical isomers of lactic acid are

1) 1
2) 2
3) 3
4) 4

Correct option: 2

Solution:
[IMAGE] Only one chiral center. Hence two optical isomers are possible.
[IMAGE] No. of optical isomer [IMAGE] (where n = no. of chiral
carbon) [IMAGE].
Subject: Chemistry — Periodic table — Electronegativity
Difficulty: Easy

Question: Correct order of electronegativity of N, P, C and Si on Pauling
scale is

1) N > P > C > Si
2) C > Si > N > P
3) N < P < C < Si
4) N > C > P > Si

Correct option: 4

Solution:
Electronegativity of elements generally increases across the
period (less increase) and decreases down the group (more decrease).
Si = 1.8, P = 2.1, C = 2.5, N = 3.
Subject: Chemistry — IUPAC Nomenclature — IUPAC-Nomenclature of Alkane & Cyclo alkane
Difficulty: Easy

Question: The correct IUPAC name of the following compound is

1) 1-Bromo-1-ethyl-2-fluoro-2-iodo-1-nitroethane.
2) 3-Bromo-4-fluoro-4-iodo-3-nitrobutane.
3) 2-Bromo-1-fluoro-1-iodo-2-nitrobutane.
4) 1-Fluoro-1-iodo-2-bromo-2-ethyl-2-nitroethane.

Correct option: 3

Solution:
Subject: Chemistry — Organic Chemistry — Biomolecules
Difficulty: Easy

Question: Proteins are built up of

1) Dicarboxylic acids
2) Amino acids
3) Alcohols
4) Hydroxy acids

Correct option: 2

Solution:
Proteins are nitrogenous compounds.
Amino acid $\rightarrow$ Dipeptide $\rightarrow$ Polypeptide
$\rightarrow$ Protein.
Subject: Chemistry — Redox Reaction — Oxidation number and Oxidation state
Difficulty: Easy

Question: The oxidation states of the most electronegative element in the
products of the reaction of BaO_2with dilute H_2SO_4are

1) 0 and -1
2) -1 and -2
3) -2 and 0
4) -2 and +1

Correct option: 2

Solution:
In H_2O_2 oxygen shows = -1(peroxide) oxidation state and in
BaO_2oxygen shows = -2 oxidation state.
Subject: Chemistry — Physical Chemistry — Chemical Equilibrium
Difficulty: Moderate

Question: The equilibrium constant for the reaction, N2 (g) + O2
(g)[IMAGE] 2NO(g) at temperature T is 4 × 10-4. The
value NO(g)[IMAGE] N2 (g) +
[IMAGE] O2 (g) at the same temperature is:
N2 (g) + O2 (g)[IMAGE] 2NO(g), bl vfHkfØ fy, rki T ij
lkE;koLFkk fLFkjkad 4 × 10-4 gS fuEu vfHkfØ fy, leku rki ij Kc dk
eku gksxk NO(g)[IMAGE] $\frac{1}{2}$N2 (g) +
$\frac{1}{2}$ O2


Answer: 50

Solution:
N2 (g) + O2 (g)[IMAGE] 2NO(g);
$K_{c} = \frac{\lbrack NO\rbrack^{2}}{\left\lbrack N_{2} \right\rbrack\left\lbrack O_{2} \right\rbrack} = 4 \times 10^{- 4}$
NO(g)[IMAGE] N2 (g) +
$K_{c} = \frac{\left\lbrack N_{2} \right\rbrack^{1/2}\left\lbrack O_{2} \right\rbrack^{1/2}}{\lbrack NO\rbrack} = \frac{1}{\sqrt{K_{0}}} = \frac{1}{\sqrt{4 \times 10^{- 4}}} = \frac{1}{2 \times 10^{- 2}} = \frac{100}{2} = 50$
Subject: Chemistry — Organic Chemistry — ALKYNE
Difficulty: Easy

Question: Identify the product D in the following series of reaction
${CH}_{3}COOH\overset{LLiHA}{\longrightarrow}A\frac{H^{+}}{443K} \rightarrow B\overset{{Br}_{2}}{\longrightarrow}C\frac{aic.}{KOH} \rightarrow D$

1) Methane
2) Alcohol
3) Acetylene
4) Benzaldehyde

Correct option: 3

Solution:
${CH}_{3} - COOH\overset{{LiAlH}_{4}}{\rightarrow}{CH}_{3} - {CH}_{2} - OH\frac{H^{+}}{443K} \rightarrow$
${CH}_{2} = {CH}_{2}\overset{{Br}_{2}}{\longrightarrow}{CH}_{2} - {CH}_{2}\frac{alc.}{KOH}$
| |
Br Br
$\begin{matrix}
 & CH \equiv CH + 2KBr + 2H_{2}O \\
 & Acetylene
\end{matrix}$
Subject: Chemistry — Inorganic Chemistry — Chemical Bonding
Difficulty: Moderate

Question: Which one of the following is an amphoteric oxide?

1) ZnO
2) Na_2O
3) SO_2
4) B_2O_3

Correct option: 1

Solution:
ZnO is an amphoteric oxide and dissolves readily in acids
forming corresponding zinc salts and alkalies forming zincates.
$ZnO + H_{2}{SO}_{4} \rightarrow {ZnSO}_{4} + H_{2}O$ zinc sulphate
$ZnO + 2NaOH \rightarrow {Na}_{2}{ZnO}_{2} + H_{2}O$ sodium zincate
Subject: Chemistry — Physical Chemistry — Ionic Equilibrium
Difficulty: Moderate

Question: The solubility product of a salt having general formula MX_2,
in water is: 4 × 10^-12. The concentration of M^2+ ions in the
saturated aqueous solution of the salt is...... × 10-4:
MX2 lw=k ds,d yo.k dk ty xq.kuQy 4 × 10-12 gSA rc yo.k ds
lar`Ir M2+ vk;uksa


Answer: 1

Solution:
MX2(s) [IMAGE] M2+ (aq) + 2X- (aq)
Ksp = s. (2s)2 = 4s3 $\Rightarrow$ 4 × 10-12 = 4s3 $\Rightarrow$ s3 =
1 × 10-12
$\Rightarrow$ s = 1 × 10-4 M $\Rightarrow$ = 1 × 10-4 M
Subject: Chemistry — Inorganic Chemistry — Periodic Properties
Difficulty: Tough

Question: A- (g) [IMAGE] A^2+ (g) [IMAGE] H
= 1100 KJ/mol
A (g) [IMAGE] A^2+ (g) [IMAGE] H = 1200
Electron gain enthalpy of A is P × 10^2 KJ/mol. What is the value of P
?



Solution:
1
A (g) [IMAGE] A- (g)
1200-1100 = 100 KJ/mol
Subject: Chemistry — Physical Chemistry — Stereoisomerism
Difficulty: Easy

Question: An enantiomerically pure acid is treated with racemic mixture of
an alcohol having one chiral carbon. The ester formed will be

1) Optically active mixture
2) Pure enantiomer
3) Meso compound
4) Racemic mixture

Correct option: 1

Solution:
When optically active acid reacts with racemic mixture of an
alcohol, it forms two types of isomeric esters. In each the
configuration of the chiral centre of acid will remain the same. So the
mixture will be optically active.
Subject: Chemistry — Inorganic Chemistry — Periodic Properties
Difficulty: Easy

Question: Consider the isoelectronic ions, K^+, S^2-, Cl^- and Ca^2+.
The radii of these ionic species follow the order

1) Ca^2+> K^+> Cl^-> S^2
2) Cl^-> S^2-> K^+> Ca^2+
3) S^2-> Cl^-> K^+> Ca^2+
4) K^+> Ca^2+> S^2-> Cl^

Correct option: 3

Solution:
For isoelectronic $Z \uparrow r \downarrow$
Subject: Chemistry — Organic Chemistry — Alcohols, Phenols and Ethers
Difficulty: Easy

Question: Phenol is treated with bromine water and shaken well. The white
precipitate formed during the process is
(a) m-bromophenol
(b) 2, 4-dibromophenol
(c) 2, 4, 6-tribromophenol
(d) A mixture of o-and p-bromophenols


Correct option: 3

Solution:
Subject: Chemistry — Physical Chemistry — Redox Reaction
Difficulty: Moderate

Question: The oxidation number of S in $H_{2}S_{2}O_{3}$ is

1) + 2
2) + 4
3) + 6
4) + 7

Correct option: 3

Solution:
The chemical structure of $H_{2}S_{2}O_{8}$ is as follows:-
[IMAGE] So the oxidation number of S should be:
[IMAGE] Or X = +6
Subject: Chemistry — Physical Chemistry — Chemical Bonding
Difficulty: Easy

Question: Consider the following statements:
I II III IV
In [IMAGE] 1. There are 6[IMAGE] and 3[IMAGE] bonds.
2. Carbon I & II are sp^2 hybridised.
3. Carbon III & IV are sp hybridised.
The above statements 1, 2, 3 respectively are (T = True, F = False)::
I II III IV
 1. ¡ 6[IMAGE] 3[IMAGE] 
2. I II sp^2 
3. III IV sp 
 1, 2 3 (T =, F = )

1) T T T (2) F T T (C) F T F
4) T F T

Answer: 2

Solution:
Subject: Chemistry — Inorganic Chemistry — Environmental Chemistry
Difficulty: Moderate

Question: Increased concentration of SO_2 and NO_2 in the atmosphere
causes

1) Acid rain
2) Global warming
3) Ozone formation
4) U.V. rays absorption

Correct option: 4

Solution:
Explanation: Sulfur dioxide and nitrogen oxides present in the
air reacts with water, oxygen etc. in atmosphere and causes acid rain by
forming acidic pollutant nitric acid, sulphuric acid etc.
Subject: Chemistry — Organic Chemistry — Hydrocarbon
Difficulty: Moderate

Question: The product formed in the reaction..
[IMAGE] is.

1) (BrCH2)3CCH2CH2C(CH2Br)3

Correct option: 4

Solution:
Subject: Chemistry — Equivalent Concept — Equivalent Concept for Redox reactions, KMnO4 / K2Cr2O7 v/s
Difficulty: Moderate

Question: Which of the following solutions will exactly oxidize 25 mL of
an acid solution of 0.1 M iron (II) oxalate

1) 25 mL of 0.1 M KMnO4
2) 25 mL of 0.2 M KMnO4
3) 25 mL of 0.6 M KMnO4
4) 15 mL of 0.1 M KMnO4

Correct option: 4

Solution:
Milli equivalents
of${FeC}_{2}O_{4} = 0.1 \times 3 \times 25 = 7.5$
From choice (D), milli equivalents of
${KMnO}_{4} = 0.1 \times 5 \times 15 = 7.5$
$$\therefore m.eq.\ of{FeC}_{2}O_{4} = m.eq.\ of{KMnO}_{4}$$
Subject: Chemistry —  — Ionic Equilibrium
Difficulty: Moderate

Question: The molar solubility (in mol L-1) of a sparingly soluble salt
MX4 is s. The corresponding solubility product is Ksp.. s is given in
terms of Ksp by the relation:,d yo.k] MX4 j foys;rk (eksy@yhVj esa) s gS rFkk
 xq.kuQy Ksp gSA fuEu lEcUèk }kjk s dks Ksp ds:i tk ldrk

1) s =
2) s = (128Ksp)1/4
3) s = (256Ksp)1/5
4) s =

Correct option: 4

Solution:
MX4 (solid) (Bksl) [IMAGE] Solubility product foys;rk xq.kuQy, Ksp = s × (4s)4 = 256 s5
$\therefore s = \left( \frac{K_{ps}}{256} \right)^{1/5}$
Physical Chemistry
Subject: Chemistry — Physical Chemistry — 
Difficulty: Easy

Question: The amount of urea to be dissolved in 500 ml of water (K =
18.6 mole^-1 in 100g solvent) to produce a depression of 0.186ºC
in freezing point.


Answer: 100

Solution:
[IMAGE] w = 3g