GATE Chemistry 2018
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GATE 2018 General Aptitude (GA) Set-4
Q. 1 – Q. 5 carry one mark each.
Q.1 “When she fell down the _______, she received many _______ but little help.”
The words that best fill the blanks in the above sentence are
(A) stairs, stares (B) stairs, stairs
(C) stares, stairs (D) stares, stares
Q.2 “In spite of being warned repeatedly, he failed to correct his _________ behaviour.”
The word that best fills the blank in the above sentence is
(A) rational (B) reasonable (C) errant (D) good
Q.3 For 0 ≤ x ≤ 2π, sin x and cos x are both decreasing functions in the interval ________.
π π 3π 3π
(A) (0, 2 ) (B) ( 2 , π) (C) (π, 2 ) (D) ( 2 , 2π)
Q.4 The area of an equilateral triangle is √3. What is the perimeter of the triangle?
(A) 2 (B) 4 (C) 6 (D) 8
Q.5 Arrange the following three-dimensional objects in the descending order of their volumes:
(i) A cuboid with dimensions 10 cm, 8 cm and 6 cm
(ii) A cube of side 8 cm
(iii) A cylinder with base radius 7 cm and height 7 cm
(iv) A sphere of radius 7 cm
(A) (i), (ii), (iii), (iv)
(B) (ii), (i), (iv), (iii)
(C) (iii), (ii), (i), (iv)
(D) (iv), (iii), (ii), (i)
Q. 6 – Q. 10 carry two marks each.
Q.6 An automobile travels from city A to city B and returns to city A by the same route. The
speed of the vehicle during the onward and return journeys were constant at 60 km/h and
90 km/h, respectively. What is the average speed in km/h for the entire journey?
(A) 72 (B) 73 (C) 74 (D) 75
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GATE 2018 General Aptitude (GA) Set-4
Q.7 A set of 4 parallel lines intersect with another set of 5 parallel lines. How many
parallelograms are formed?
(A) 20 (B) 48 (C) 60 (D) 72
Q.8 To pass a test, a candidate needs to answer at least 2 out of 3 questions correctly. A total of
6,30,000 candidates appeared for the test. Question A was correctly answered by 3,30,000
candidates. Question B was answered correctly by 2,50,000 candidates. Question C was
answered correctly by 2,60,000 candidates. Both questions A and B were answered
correctly by 1,00,000 candidates. Both questions B and C were answered correctly by
90,000 candidates. Both questions A and C were answered correctly by 80,000 candidates.
If the number of students answering all questions correctly is the same as the number
answering none, how many candidates failed to clear the test?
(A) 30,000 (B) 2,70,000 (C) 3,90,000 (D) 4,20,000
1
Q.9 If x 2 + x − 1 = 0 what is the value of x 4 + ?
x4
(A) 1 (B) 5 (C) 7 (D) 9
Q.10 In a detailed study of annual crow births in India, it was found that there was relatively no
growth during the period 2002 to 2004 and a sudden spike from 2004 to 2005. In another
unrelated study, it was found that the revenue from cracker sales in India which remained
fairly flat from 2002 to 2004, saw a sudden spike in 2005 before declining again in 2006.
The solid line in the graph below refers to annual sale of crackers and the dashed line refers
to the annual crow births in India. Choose the most appropriate inference from the above
data.
(A) There is a strong correlation between crow birth and cracker sales.
(B) Cracker usage increases crow birth rate.
(C) If cracker sale declines, crow birth will decline.
(D) Increased birth rate of crows will cause an increase in the sale of crackers.
END OF THE QUESTION PAPER
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GATE 2018 CHEMISTRY
Q. 1 – Q. 25 carry one mark each.
Q.1 The major product formed in the following reaction is
(A) (B)
(C) (D)
Q.2 The major product formed in the following reaction is
(A) (B)
(C) (D)
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GATE 2018 CHEMISTRY
Q.3 The major product of the following intramolecular cycloaddition reaction is
(A) (B)
(C) (D)
Q.4 The major product of the following reaction is
(A) (B)
(C) (D)
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GATE 2018 CHEMISTRY
Q.5 The major product formed in the following reaction sequence is
(A) (B)
(C) (D)
Q.6 The major product formed in the following reaction sequence is
(A) (B)
(C) (D)
Q.7 The spherical harmonic function, Yl ,m ( , ) , with appropriate values of l and m, is an
eigenfunction of Lˆx 2 Lˆ y 2 operator. The corresponding eigenvalue is
(A) l l 1 m 2 2
(B) l l 1 m2 2
(C) l l 1 2
(D) m 2 2
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GATE 2018 CHEMISTRY
Q.8 1 1
Consider the operators, aˆ xˆ ipˆ x and aˆ xˆ ipˆ x , where x̂ and pˆ x are the
2 2
position and linear momentum operators, respectively. The commutator, [aˆ , aˆ ] is equal to
(A) i (B) i
(C) (D)
Q.9 E
The temperature derivative of electrochemical cell potential E at constant pressure, ,
T P
is given by
S S
(A) (B)
nF nF
S S
(C) (D)
nFT nFT
Q.10 For an ionic micelle-forming surfactant near its critical micelle concentration (CMC), the
dependence of molar conductivity and surface tension on surfactant concentration is best
represented by
(A) (B)
(C) (D)
Q.11 According to Eyring transition state theory for a bimolecular reaction, the activated
complex has
(A) no vibrational degrees of freedom.
(B) vibrational degrees of freedom but they never participate in product formation.
(C) one high frequency vibration that leads to product formation.
(D) one low frequency vibration that leads to product formation.
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GATE 2018 CHEMISTRY
Q.12 Based on Wade’s rule, the structure-type of [B5H8]– is
(A) closo (B) nido (C) arachno (D) hypho
Q.13 The coordination geometries around the copper ion of plastocyanin (a blue-copper protein)
in oxidized and reduced form, respectively, are
(A) tetrahedral and square-planar
(B) square-planar and tetrahedral
(C) distorted tetrahedral for both
(D) ideal tetrahedral for both
Q.14 The water exchange rates for the complex ions follow the order
(A) [V(H2O)6]2+ > [Co(H2O)6]2+ > [Cr(H2O)6]3+
(B) [Cr(H2O)6]3+ > [Co(H2O)6]2+ > [V(H2O)6]2+
(C) [Co(H2O)6]2+ > [Cr(H2O)6]3+ > [V(H2O)6]2+
(D) [Co(H2O)6]2+ > [V(H2O)6]2+ > [Cr(H2O)6]3+
Q.15 The lowest energy d d transition of the complexes follow the order
(A) [Cr(H2O)6]3+ < [Cr(NH3)6]3+ < [Cr(CN)6]3–
(B) [Cr(CN)6]3– < [Cr(NH3)6]3+ < [Cr(H2O)6]3+
(C) [Cr(CN)6]3– < [Cr(H2O)6]3+ < [Cr(NH3)6]3+
(D) [Cr(NH3)6]3+ < [Cr(CN)6]3– < [Cr(H2O)6]3+
Q.16 The symmetry label of valence p orbitals of a metal ion in an octahedral ligand field is
(A) t1g (B) t1u (C) eg + a1g (D) t2g
Q.17 The bond angle (TiCC) in the crystal structure of
is severely distorted due to
(A) hydrogen-bonding interaction
(B) agostic interaction
(C) steric bulk of the phosphine ligand
(D) higher formal charge on metal
Q.18 The molar heat capacity of a substance is represented in the temperature range 298 K to
400 K by the empirical relation C p ,m 14 bT J K–1 mol–1, where b is a constant. The
molar enthalpy change when the substance is heated from 300 K to 350 K is 2 kJ mol–1.
The value of b is___________ J K–2 mol–1. (Up to two decimal places)
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GATE 2018 CHEMISTRY
Q.19 For low partial pressure of ozone (O3), the adsorption of ozone on graphite surface is fully
dissociative in nature, and follows Langmuir isotherm. Under these conditions, if the
dependence of the surface coverage of graphite (θ) on partial pressure of ozone PO3 is
, the value of x is___________. (Up to two decimal places)
x
given by PO3
Q.20 For the radioactive isotope 131I, the time required for 50% disintegration is 8 days. The time
required for the 99.9% disintegration of 5.5 g of 131I is ________ days. (Up to one decimal
place)
Q.21 Two moles of an ideal gas X and two moles of an ideal gas Y, initially at the same
temperature and pressure, are mixed under isothermal-isobaric condition. The entropy
change on mixing is __________J K–1. (Up to one decimal place. Use R = 8.31 J K–1 mol–1)
Q.22 The energy of a hydrogen molecule in its ground state equilibrium configuration is –31.7 eV.
Its dissociation energy is _________ eV. (Up to one decimal place)
Q.23 The total number of valence electrons in W(η3-Cp)(η5-Cp)(CO)2 is ______. (Atomic number
of W = 74)
Q.24 In the 1H NMR spectrum of an organic compound recorded on a 300 MHz instrument, a
proton resonates as a quartet at 4.20 ppm. The individual signals of the quartet appear
at 4.17, 4.19, 4.21 and 4.23 ppm. The coupling constant J in Hz is ______.
Q.25 In the electron ionization (EI) mass spectra, methyl hexanoate, methyl heptanoate and methyl
octanoate give the same base peak. The m/z value of the base peak is ______.
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GATE 2018 CHEMISTRY
Q. 26 – Q. 55 carry two marks each.
Q.26 In the following reaction,
(A) X is the major product and Y is the minor product
(B) X is the only product
(C) Y is the only product
(D) X is the minor product and Y is the major product
Q.27 The enantiomeric pair, among the following, is
(A) (B)
(C) (D)
Q.28 The major product formed in the following reaction sequence is
(A) (B)
(C) (D)
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GATE 2018 CHEMISTRY
Q.29 The major product in the following reaction sequence is
(A) (B)
(C) (D)
Q.30 The major product formed in the following reaction sequence is
(A) (B)
(C) (D)
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GATE 2018 CHEMISTRY
Q.31 The major product of the following reaction sequence is
(A) (B)
(C) (D)
Q.32 The major product formed in the following retro-aldol reaction is
(A) (B)
(C) (D)
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GATE 2018 CHEMISTRY
Q.33 The elimination product of the following reaction is
(A) I2 (B) CH3I (C) CH3COI (D) I3–
Q.34 A one-dimensional anharmonic oscillator is treated by perturbation theory. The harmonic
1
oscillator is used as the unperturbed system and the perturbation is x 3 ( is a constant).
6
Using only the first order correction, the total ground state energy of the anharmonic
oscillator is
k
1/4 1/2
(Note: For a one-dimensional harmonic oscillator 0 x e x ; 2 )
2
1/2 1/2
1 k 1 k
(A) (B)
2 2 6
1/2 1/2
1 k 1 k
(C) (D)
2 3 2 12
Q.35 The O2 coordinated to metal ion centres in oxy-myoglobin and oxy-hemocyanin exists,
respectively, as
(A) superoxide and peroxide
(B) superoxide and superoxide
(C) peroxide and peroxide
(D) superoxide and oxygen
Q.36 Spectroscopic ground state term symbols of cobalt ions in [Co(H2O)6]2+ and [CoCl4]2–,
respectively, are
(A) 2T1g and 4A2 (B) 4T1g and 4A2
(C) 4T2g and 4T1 (D) 2T1 and 4A1
Q.37 Generally, the coordination number and the nature of the electronic absorption band (f f
transition) of lanthanide(III) ion in their complexes are, respectively,
(A) greater than 6 and sharp (B) 6 and broad
(C) less than 6 and sharp (D) greater than 6 and broad
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GATE 2018 CHEMISTRY
Q.38 Second-order rate constant for the reaction between [Co(NH3)5X]n+ (n = 3 for X = NH3 and
H2O; n = 2 for X = Cl–) and [Cr(H2O)6]2+ at room temperature varies with the X as
(A) NH3 > H2O > Cl– (B) Cl– > H2O > NH3
(C) NH3 > Cl– > H2O (D) H2O > NH3 > Cl–
Q.39 For the following reaction sequence,
X and Y, respectively, are
(A) {HB(NH)}3 and {H(OH)B(NH2)}3
(B) {HB(NH)}3 and {HB(NH2OH)}3
(C) (NH4){(H)2(BH2)3} and {H(OH)(NH2OH)}3
(D) (NH4){(H)2(BH2)3} and {HB(NH2OH)}3
Q.40 For an inverse spinel, AB2O4, the A and B, respectively, can be
(A) Ni(II) and Ga(III) (B) Zn(II) and Fe(III)
(C) Fe(II) and Cr(III) (D) Mn(II) and Mn(III)
Q.41 The reaction of PCl3 with PhLi in 1:3 molar ratio yields X as one of the products, which on further
treatment with CH3I gives Y. The reaction of Y with n-BuLi gives product Z. The products X, Y
and Z, respectively, are
(A) [PPh4]Cl, [Ph2P=CH2] and Ph2P(n-Bu)
(B) PPh3, [Ph3PI](CH3) and Ph2P(n-Bu)3
(C) PPh3, [Ph3P(CH3)]I and Ph3P=CH2
(D) [PPh4]Cl, [Ph3P=CH2] and [Ph3P(n-Bu)]Li
Q.42 The reaction of equimolar quantities of Fe(CO)5 and OH– gives a complex species X which
on further reaction with MnO2 gives species Y. X and Y, respectively, are
(A) [Fe(CO)5(OH)]– and Fe2(CO)9
(B) [Fe(CO)4]2– and Mn2(CO)10
(C) [HFe(CO)4]– and Fe2O3
(D) [HFe(CO)4]– and Fe3(CO)12
Q.43 The rate constant of a first order reaction, X Y , is 1.6 10–3 s–1 at 300 K. Given that
the activation energy of the reaction is 28 kJ mol–1 and assuming Arrhenius behavior for
the temperature dependence, the total time required to obtain 90% of Y at 350 K
is_____________ s. (Up to one decimal place. Use R = 8.31 J K–1 mol–1 )
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GATE 2018 CHEMISTRY
Q.44 The molar conductivity of a 0.01 M weak acid (HX) at 298 K, measured in a conductivity
cell with cell constant of 0.4 cm–1, is 64.4 S cm2 mol–1. The limiting molar conductivities at
infinite dilution of H+ and X– at 298 K are 350 and 410 S cm2 mol–1, respectively. Ignoring
activity coefficients, the pKa of HX at 298 K is___________. (Up to two decimal places)
Q.45 The Latimer diagram of oxygen is given below. The value of x is ________ V. (Up to two
decimal places)
Q.46 At temperature T, the canonical partition function of a harmonic oscillator with fundamental
frequency (ν) is given by
e h /2kBT
qvib (T )
1 e h / kBT
h
For 3 , the probability of finding the harmonic oscillator in its ground vibrational
k BT
state is ________. (Up to two decimal places)
Q.47 The enthalpy of vaporization of a liquid at its boiling point ( Tb 200 K ) is 15.3 kJ mol–1. If
the molar volumes of the liquid and the vapour at 200 K are 110 and 12000 cm3 mol–1
dP
respectively, then the slope of the liquid-vapour boundary is _________ kPa K–1. (Up
dT
to two decimal places. Note: 1 Pa = 1 J m–3)
Q.48 In a molecule XY, let X and Y denote normalized atomic orbitals of atoms X and Y,
respectively. A normalized molecular orbital of XY is given by 0.56( X Y ) . The
value of the overlap integral of X and Y is _________________. (Up to two decimal
places)
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GATE 2018 CHEMISTRY
Q.49 The absorption maxima of two dyes X and Y are 520 and 460 nm, respectively. The
absorbance data of these dyes measured in a 1 cm path length cell are given in the table
below.
Dye solution Absorbance Absorbance
at 460 nm at 520 nm
X (9 mM) 0.144 0.765
Y (12 mM) 0.912 0.168
Mixture of X and Y 0.700 0.680
The concentration of Y in the mixture is __________ mM. (Up to two decimal places)
Q.50 The π electrons in benzene can be modelled as particles in a ring that follow Pauli’s
exclusion principle. Given that the radius of benzene is 1.4 Å, the longest wavelength of
light that is absorbed during an electronic transition in benzene is __________ nm. (Up to
one decimal place. Use me 9.11031 kg, h 6.6 1034 J s, c 3.0 108 m s 1 )
Q.51 The spacing between the two adjacent lines of the microwave spectrum of H35Cl is
6.35 1011 Hz . Given that the bond length of D35Cl is 5% greater than that of H35Cl, the
corresponding spacing for D35Cl is _______ 1011 Hz. (Up to two decimal places)
Q.52 For a diatomic vibrating rotor, in vibrational level = 3 and rotational level J, the sum of
the rotational and vibrational energies is 11493.6 cm–1. Its equilibrium oscillation
frequency is 2998.3 cm–1, anharmonicity constant is 0.0124 and rotational constant under
rigid rotor approximation is 9.716 cm–1. The value of J is ___________. (Up to nearest
integer)
Q.53 Number of carbonyl groups present in the final product of the following reaction sequence
is ___________.
Q.54 A tetrapeptide, made up of natural amino acids, has alanine as the N-terminal residue
which is coupled to a chiral amino acid. Upon complete hydrolysis, the tetrapeptide gives
glycine, alanine, phenylalanine and leucine. The number of possible sequences of the
tetrapeptide is ____.
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GATE 2018 CHEMISTRY
Q.55 The strongest band observed in the IR spectrum of the final product of the following
reaction appears, approximately, at ______ × 100 cm–1. (Up to one decimal place)
END OF THE QUESTION PAPER
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Q.No. Type Section Key/Range Marks 1 MCQ GA A 1 2 MCQ GA C 1 3 MCQ GA B 1 4 MCQ GA C 1 5 MCQ GA D 1 6 MCQ GA A 2 7 MCQ GA C 2 8 MCQ GA D 2 9 MCQ GA C 2 10 MCQ GA A 2 1 MCQ CY C 1 2 MCQ CY D 1 3 MCQ CY D 1 4 MCQ CY B 1 5 MCQ CY B 1 6 MCQ CY A 1 7 MCQ CY A 1 8 MCQ CY C 1 9 MCQ CY B 1 10 MCQ CY B 1 11 MCQ CY D 1 12 MCQ CY B 1
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Q.No. Type Section Key/Range Marks 13 MCQ CY C 1 14 MCQ CY D 1 15 MCQ CY A 1 16 MCQ CY B 1 17 MCQ CY B 1 18 NAT CY 0.07 to 0.09 1 19 NAT CY 0.32 to 0.34 1 20 NAT CY 79.1 to 80.6 1 21 NAT CY 22.0 to 24.0 1 22 NAT CY 4.4 to 4.6 1 23 NAT CY 18.0 to 18.0 1 24 NAT CY 6.0 to 6.0 1 25 NAT CY 73.8 to 74.2 1 26 MCQ CY A 2 27 MCQ CY D 2 28 MCQ CY A 2 29 MCQ CY A 2 30 MCQ CY D 2 31 MCQ CY D 2 32 MCQ CY B 2 33 MCQ CY C 2 34 MCQ CY A 2
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Q.No. Type Section Key/Range Marks 35 MCQ CY A 2 36 MCQ CY B 2 37 MCQ CY A 2 38 MCQ CY B 2 39 MCQ CY A 2 40 MCQ CY A 2 41 MCQ CY C 2 42 MCQ CY D 2 43 NAT CY 280 to 300 2 44 NAT CY 4.01 to 4.21 2 45 NAT CY 1.22 to 1.24 2 46 NAT CY 0.93 to 0.97 2 47 NAT CY 6.20 to 6.60 2 48 NAT CY 0.55 to 0.65 2 49 NAT CY 7.4 to 8.2 2 50 NAT CY 210.0 to 216.0 2 51 NAT CY 2.80 to 3.10 2 52 NAT CY 12 to 12 2 53 NAT CY 4.0 to 4.0 2 54 NAT CY 4.0 to 4.0 2 55 NAT CY 16.99 to 17.31 2
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Source: GATE. Question paper published by GATE.