datavorous/entrance-exam-dataset huggingface dataset:
The number of protons, neutrons and electrons in 71175Lu, respectively, are

Options:
A 104, 71 and 71
B 71, 71 and 104
C 175, 104 and 71
D 71, 104 and 71

The correct answer is:
71, 104 and 71

Solution:
Lu71175

protons=71

neutrons=mass number-protons=175−71=104

electrons=71

Topic: Chemistry, Structure of Atom, NEET, NEET 2020 (Phase 1)
The number of revolutions done by an electron in one second in the first orbit of a hydrogen atom is

Options:
A 6.57×1015
B 6.57×1013
C 6.57×1011
D 6.57×1014

The correct answer is:
6.57×1015

Solution:
Ï1t=n.(2Ïr1)
We know that frequency=velocitydistance
v12Ïr1=2.18Ã1062ÏÃ0.529Ã10-10
=6.57Ã1015

Topic: Physics, Atomic Physics, NEET
The number of sp2 hybrid orbitals in a molecule of benzene is

Options:
A 18
B 6
C 12
D 24

The correct answer is:
18

Solution:
Benzene: C6H6
As in Benzene, Each carbon is sp2 Hybridized
Total number of carbon =6(sp2 Hybridized)
In one sp2 hybrid. number of orbitals = 3
Hence total Hybrid orbitals =6×3=18

Topic: Chemistry, General Organic Chemistry, NEET
The number of sp2 hybridised carbon atoms present in "Aspartame" are?

Options:
A 6
B 7
C 9
D 10

The correct answer is:
9

Solution:
There are 9 sp2 hybridised carbon atoms present in "Aspartame" shown by ⋅ (dot) here.

Topic: Chemistry, Chemistry in Everyday Life, NEET
The number of S-S bonds in sulphur trioxide trimer S3O9 is

Options:
A 3
B 2
C 1
D 0

The correct answer is:
0

Solution:
The cyclic trimer of SO3 is S3O9

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
The number of sex chromosomes is found to be normal in

Options:
A Super female
B Turner's syndrome
C Klinefelter's syndrome
D Down's syndrome

The correct answer is:
Down's syndrome

Solution:
Down's syndrome is an autosomal aneuploidy. It is a trisomy of the 21st chromosome. Turner's, Klinefelter's syndrome and super female are chromosomal disorders involving the X chromosome.
Turner's syndrome - one X chromosome is missing
Klinefelter's syndrome - one extra copy of X chromosome in males
Super female - three copies of X chromosome in females

Topic: Biology, Principles of Inheritance and Variation, NEET
The number of sigma σ and pi π bonds in pent- 2 -en- 4 -yne is:

Options:
A 10 σ bonds and 3 π bonds
B 8 σ bonds and 5 π bonds
C 11Â Ï bonds and 2 Â Ï bonds
D 13Â Ï bonds and no Ï bonds

The correct answer is:
10 σ bonds and 3 π bonds

Solution:
Pent-2-en-4-yne

The correct name should be Pent-3-en-1-yne

Number of π bonds =3

Number of σ bonds =10

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET, NEET 2019 (All India)
The number of significant figures in 45056 is

Options:
A 2
B 3
C 4
D 5

The correct answer is:
5

Solution:
All the figures, in this case, are significant.
Note- zeroes between two non zero digits are always significant.

Topic: Physics, Units and Dimensions, NEET
The number of stereo isomers possible for a compound of the molecular formula CH3-CH=CH-CH(OH)-CH3 is:

Options:
A 2
B 4
C 6
D 3

The correct answer is:
4

Solution:
As about the double bond, two geometrical isomers are possible and the compound is having one chiral carbon atom so there are two optical isomers . It means it has four stereo isomers.
CH3-CH=CH-*CH(OH)-CH3
Total G.I = 2n=21=2
Total O.I = 2n=21=2
Here n = number of double bonds or number of chiral carbon atoms.

Topic: Chemistry, General Organic Chemistry, NEET
The number of structural isomers for C6H14 is

Options:
A 6
B 3
C 4
D 5

The correct answer is:
5

Solution:
C6H14 has 5 structural isomers which are as follows

Topic: Chemistry, General Organic Chemistry, NEET
The number of structural isomers for C6H14 is:

Options:
A 4
B 5
C 6
D 3

The correct answer is:
5

Solution:

Topic: Chemistry, General Organic Chemistry, NEET
The number of substrate-level phosphorylation in one turn of citric acid cycle is:

Options:
A One
B Two
C Three
D Zero

The correct answer is:
One

Solution:
Substrate-level phosphorylation: In the presence of the enzyme succinyl CoA synthetase or succinyl thiokinase, succinyl CoA is converted into succinate, producing GTP as the source of energy. This GTP then in the presence of phosphokinase gets converted into ATP.

Succinyl CoA + GDP + Pi →Succinyl CoA synthetase/Succinyl thiokinase Succinate + GTP + CoA

Topic: Biology, Respiration in Plants, NEET, NEET 2020 (Phase 1)
The number of three centre two electron bonds in a molecule of diborane is

Options:
A 0
B 2
C 4
D 6

The correct answer is:
2

Solution:
The number of three centre two electrons bonds in a molecule of diborane is 2.

Topic: Chemistry, p Block Elements (Group 13 & 14), NEET
The number of time(s) decarboxylation of isocitrate occurs during single TCA cycle is :

Options:
A One
B Two
C Three
D Four

The correct answer is:
Two

Solution:
Isocitrate (Isocitric acid) undergoes two times decarboxylation during TCA cycle. During first decarboxylation, it forms $\alpha$-Ketoglutaric acid and in the second time, it forms succinyl Co-A

Topic: Biology, Respiration in Plants, NEET, NEET 2022 (Phase 2)
The number of unpaired electrons calculated in [CoNH36]3+and CoF63- are

Options:
A 4 and 4
B 0 and 2
C 2 and 4
D 0 and 4

The correct answer is:
0 and 4

Solution:
In both CoNH363+ and CoF63+, Co is present as Co3+.
Thus, the electronic configuration of Co is
Co=[Ar] 3d7,4s2
Co3+=[Ar]3d6, 4s0
In case of CoNH363+, NH3 is a strong field ligand, so pairing of electrons in 3d-orbital takes place.
Co3+=[Ar]3d6, 4s0
In CoF63+, F is a weak field ligand, thus doesn't cause pairing. Hence,
Co3+=[Ar]3d6, 4s0

Topic: Chemistry, Coordination Compounds, NEET
The number of unpaired electrons in a paramagnetic diatomic molecule of an element with atomic number 16 is:

Options:
A 1
B 2
C 3
D 4

The correct answer is:
2

Solution:
According to MOT, Sulphur have two unpaired electrons.
Caution
Because of the presence of two unpaired electrons, it shows paramagnetic character

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET, NEET 2006
The number of unpaired electrons in [Ni(CO)4] is

Options:
A one
B two
C three
D zero

The correct answer is:
zero

Solution:
Ni(Z=28):3d84s2
Oxidation state of Ni in [Ni(CO)4)]=0

Number of unpaired electrons = 0.

Topic: Chemistry, Coordination Compounds, NEET
The number of unpaired electrons in tetrahedral [Ni(CO)4] is

Options:
A 0
B 2
C 3
D 4

The correct answer is:
0

Solution:
There are zero unpaired electrons in [Ni(CO)4] as inner 3d electrons get paired due to strong ligand CO.

Topic: Chemistry, d and f Block Elements, NEET
The number of unpaired electrons in the complex ion $\left[\mathrm{CoF}_6\right]^{3-}$ is:
(Atomic no. : $\mathrm{Co}=27$ )

Options:
A 2
B 3
C 4
D Zero

The correct answer is:
4

Solution:
\(\mathrm{Co}(\mathrm{Z}=27)\) has observed electronic configuration \([\mathrm{Ar}] 3 \mathrm{~d}^7 4 \mathrm{~s}^2 . \mathrm{Co}^{3+}\) has electronic configuration \([\mathrm{Ar}] 3 \mathrm{~d}^6 4 \mathrm{~s}^0 \cdot\left[\mathrm{CoF}_6\right]^{3-}\) is a high spin complex and contains 4 unpaired electrons.

Topic: Chemistry, Coordination Compounds, NEET, NEET 2003
The number of vertebrochondral ribs in human is

Options:
A 2
B 4
C 6
D 14

The correct answer is:
6

Solution:
Ribs are of 3 types:
1. True ribs (First 7 pairs) :Dorsally attached to the thoracic vertebrae and ventrally connected to the sternum with the help of hyaline cartilage.
2. Vertebrochondral or False ribs (8th, 9th and 10th pairs): These ribs do not articulate directly with the sternum but join the 7th rib with the help of hyaline cartilage.
3. Floating ribs (11th and 12th pairs): These ribs are not connected ventrally.

Topic: Biology, Locomotion and Movement, NEET
The number of water molecules is maximum in

Options:
A 18 molecules of water.
B 1.8 gram of water.
C 18 gram of water.
D 18 moles of water.

The correct answer is:
18 moles of water.

Solution:
18 grams of water corresponds to 1 mole and contains =6.02×1023 water molecules.
18 moles of water contains=18 ×6.02×1023 water molecules.
18 molecules of water
1.8 grams of water contain 1.818×NA=0.1NA water molecules.

So, 18 mole water has a maximum number of molecules.

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET, NEET 2015 (Phase 2)
The number of waves made by a Bohr electron in an orbit of maximum magnetic quantum number +2 is

Options:
A 3
B 0
C 2
D 1

The correct answer is:
3

Solution:
For ml=+2 (maximum)
l=2
As l = 2 so minimum value of n is 3
Hence number of waves in a shell = n = 3.

Topic: Chemistry, Structure of Atom, NEET
The $\mathrm{OH}$ group of an alcohol or the$\mathrm{COOH}$ group of a carboxylic acid can be replaced by $-\mathrm{Cl}$ using:

Options:
A phosphorus pentachloride
B hypochlorous acid
C chlorine
D hydrochloride acid

The correct answer is:
phosphorus pentachloride

Solution:
$\mathrm{PCl}_5$ on reaction with alcohol and carboxylic acid, replace $-\mathrm{OH}$ group with $-\mathrm{Cl}$.
$$
\begin{aligned}
\mathrm{ROH}+\mathrm{PCl}_5 \longrightarrow \mathrm{RCl} & +\mathrm{POCl}_3+\mathrm{HCl} \\
\mathrm{RCOOH}+\mathrm{PCl}_5 \longrightarrow & \mathrm{RCOCl}^2 \\
+ & \mathrm{POCl}_3+\mathrm{HCl}
\end{aligned}
$$
Related Theory
$\mathrm{PCl}_5$ is used as a chlorinating agent and dehydrating agent for the synthesis of pesticides, phosphite antioxidants, plasticizers and stabilizers for plastic and elastomers etc

Topic: Chemistry, Carboxylic Acid Derivatives, NEET, NEET 2004
The Okazaki fragments in DNA chain growth:

Options:
A polymerize in the 3 ' to $5^{\prime}$ direction and replication fork
B prove semi-conservative nature of DNA replication
C polymerize in the $5^{\prime}$ to 3 ' direction and explain 3' to 5' DNA replication
D result in transcription.

The correct answer is:
polymerize in the $5^{\prime}$ to 3 ' direction and explain 3' to 5' DNA replication

Solution:
Okazaki fragments in DNA are linked up by the enzyme DNA ligase after replacing the RNA primers with deoxyribonucleotides after replacing the $\mathrm{RNA}$ primers with deoxyribonucleotides solution of the Okazaki fragments in DNA chain growth. Replication occurs always in 5'-3' direction. However, Okazaki fragments are synthesized on 3'-5' DNA template, join to form lagging strand which grows in $3^{\prime}-5^{\prime}$ direction.

Topic: Biology, Molecular Basis of Inheritance, NEET, NEET 2007
The one aspect which is not a salient feature of genetic code, is its being

Options:
A degenerate
B ambiguous
C universal
D specific

The correct answer is:
ambiguous

Solution:
Genetic codes are never ambiguous. That is, it is never confusing. It is represented as triplet codons, each represents an amino acid. There are 64 codons. Out of which 61 codes for amino acids and 3 are stop codons.

Topic: Biology, Molecular Basis of Inheritance, NEET, NEET 2010 (Screening)
The one electron species having ionisation energy of 54.4 eV is

Options:
A He+
B H
C Be2+
D Be3+

The correct answer is:
He+

Solution:
Ionisation energy =-13.6Z2n2eV
=-13.6Ã2212 (For He+, Z=2)
=-54.4 eV

Topic: Chemistry, Structure of Atom, NEET
The one which is tetrabasic is :

Options:
A Ortho phosphorus acid
B Ortho phosphoric acid
C Meta phosphoric acid
D Pyro phosphoric acid

The correct answer is:
Pyro phosphoric acid

Solution:
H4P2O7 is tetrabasic because it gives four H+ ions when dissolved in water.
O O HO - P | | | - O - P | | | - OH OH OH

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
The one-dimensional motion of a point particle is shown in the figure. Select the correct statement.

Options:
A The total distance travelled by the particle is zero
B The total displacement of the particle is zero
C The maximum acceleration of the particle is 12 m s-2
D The total distance travelled by the particle at the end of 10 s is 100 m

The correct answer is:
The total displacement of the particle is zero

Solution:
Given, the figure shows the relation between speed and time. So, the area of the figure will be displacement.
Therefore,
area of first triangular d1=12×10×10=50 m , area of second triangular
d2=12×-10×10=-50 m
Therefore, the total area d= total displacement of the particle
⇒d1+d2=50-50=0

Topic: Physics, Motion In One Dimension, NEET
The one-horned rhinoceros is specific to which of the following sanctuary

Options:
A Bhitar Kanika
B Bandipur
C Kaziranga
D Corbett park

The correct answer is:
Kaziranga

Solution:
The one-horned rhinoceros is specific to Kaziranga.

Topic: Biology, Biodiversity and its Conservation, NEET
The one-quarter section is cut from a uniform circular disc of the radius R. This section has a mass M. It is made to rotate about a line perpendicular to its plane and passing through the centre of the original disc. Its moment of inertia about the axis of rotation is

Options:
A 1 2 MR 2
B 1 4 MR 2
C 1 8 MR 2
D 2 MR 2

The correct answer is:
1 2 MR 2

Solution:
Mass of the whole disc = 4 M
Moment of inertia of the disc about the given axis
= 1 2 4 M R 2 = 2 MR 2
∴ Moment of inertia of quarter section of the disc
= 1 4 2 MR 2 = 1 2 MR 2

Topic: Physics, Rotational Motion, NEET
The only first row transition metals that makes halides in its +1 state is:

Options:
A Sc
B V
C Zn
D Cu

The correct answer is:
Cu

Solution:
Correct Option is : 4
Cu

Topic: Chemistry, d and f Block Elements, NEET
The open-chain glucose, (an aldohexose) and fructose (a 2-oxohexose) have .... and ..... chiral carbons respectively.

Options:
A 4, 4
B 4, 3
C 3, 3
D 3, 4

The correct answer is:
4, 3

Solution:
Open-chain glucose, HOCH2CHOH*CHOH*CHOH*CHOH*CHO has, four chiral carbons (asterisked carbons) and open-chain fructose, HOCH2CHOH*CHOH*CHOH*COCH2OH has three chiral carbons.

Topic: Chemistry, Biomolecules, NEET
The operating point of transistor amplifier should be in

Options:
A middle of its active region
B middle of its saturation region
C middle of its cut-off region
D between the cut-off and active region

The correct answer is:
middle of its active region

Solution:
The operating point of transistor amplifier should be in the middle of its active region.

Topic: Physics, Semiconductors, NEET
The operating point of transistor amplifier should be in

Options:
A middle of its active region
B middle of its saturation region
C middle of its cut-off region
D between the cut-off and active region

The correct answer is:
middle of its active region

Solution:
The operating point of transistor amplifier should be in middle of its active region.

Topic: Physics, Semiconductors, NEET
The optical rotation of the α- form of a pyranose is +150.70 , that of the β- form is +52.80 . In solution an equilibrium mixture of the anomers has an optical rotation of +80.20 . The percentage of the α- form at equilibrium is

Options:
A 28%
B 32%
C 68%
D 72%

The correct answer is:
28%

Solution:
=105.7x−5220−52.x=8220
x= 2800 98.5 =28.4

Topic: Chemistry, General Organic Chemistry, NEET
The option depicting the correct partial pressures (in mm Hg) is:

Options:
A

pO2 in alveolar air	pCO2 in deoxygenated blood	pO2 in oxygenated blood	pCO2 in tissues

104	40	94	45

B

pO2 in alveolar air	pCO2 in deoxygenated blood	pO2 in oxygenated blood	pCO2 in tissues

94	45	104	40

C

pO2 in alveolar air	pCO2 in deoxygenated blood	pO2 in oxygenated blood	pCO2 in tissues

104	40	94	40

D

pO2 in alveolar air	pCO2 in deoxygenated blood	pO2 in oxygenated blood	pCO2 in tissues

104	45	94	45

The correct answer is:

pO2 in alveolar air	pCO2 in deoxygenated blood	pO2 in oxygenated blood	pCO2 in tissues

104	45	94	45

Solution:
Partial pressure which is the pressure contributed by a single gas alone in the mixture of gases. It is represented as pG, where G represents different gases. The table gives us the pressures of oxygen and carbon-di-oxide during the exchange of gases from alveoli to blood and blood to the tissues. Carbon-di-oxide has a higher solubility in the blood (20-25) times than that of oxygen due to which the partial pressure of CO2 is lower as compared to oxygen.

Topic: Biology, Breathing and Exchange of Gases, NEET
The option that represents correct molarity (M) and molality (m) respectively for HCl solution, if 36.5% HCl solution has a density equal to 1.2gml-1 is:

Options:
A 15.7, 15.7
B 12, 12
C 15.7, 12
D 12, 15.7

The correct answer is:
12, 15.7

Solution:
The relation between Molarity M and % mass:
M=%byweightÃ10ÃdM.w=36.5Ã10Ã1.236.5=12 M
The relation between molality (m) and mass(%):
mâ=â (w/w%)âÃâ100 M 2 âÃâ(100âw/w%) m=36.5Ã100036.5Ã(100-36.5)=100063.5=15.7 m

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET
The oral contraceptive developed by CDRI has lesser side effects because it

Options:
A contains a non-steroidal preparation.
B contains both estrogen and progesterone.
C inhibits ovulation and implantation.
D has to be taken for a period of 21 days.

The correct answer is:
contains a non-steroidal preparation.

Solution:
Oral administration of small doses of either progestogens or progestogenâestrogen combinations is another contraceptive method used by the females. They inhibit ovulation and implantation as well as alter the quality of cervical mucus to prevent/retard entry of sperms. Pills are very effective with lesser side effects and are well accepted by the females. Saheli, a new oral contraceptive for the females, contains a non-steroidal preparation. It is a âonce a weekâ pill with very few side effects and high contraceptive value.

Topic: Biology, Reproductive Health, NEET
The orbital angular momentum of an electron in 2s -orbital is

Options:
A 12h2π
B h2π
C 2h2π
D Zero

The correct answer is:
Zero

Solution:
Since s-orbital have l=0
Angular momentum= l(l+1)×h2π = 0×h2π=0

Topic: Chemistry, Structure of Atom, NEET
The orbital diagram in which both the Pauli exclusion principle and Hund's rule are violated is

Options:
A
B
C
D

The correct answer is:

Solution:
The orbital diagram in which both the Pauli exclusion principle and Hund's rule are violated is
The s-orbital is containing two electrons with parallel spins and in p-sub shell all the p-orbital are not first singly filled. According to Hund's rule, pairing starts only after equal energy orbitals get singly filled.

Topic: Chemistry, Structure of Atom, NEET
The orbital diagram in which both the Pauli's exclusion principle and Hund's rule are violated

Options:
A

B

C

D

The correct answer is:

Solution:
Both the Pauli's exclusion principle and Hund's rule are violated.

Topic: Chemistry, Structure of Atom, NEET
The orbital frequency of an electron in the hydrogen atom is proportional to

Options:
A n3
B n-3
C n⁡
D n0

The correct answer is:
n-3

Solution:
The time period of the electron, T=4ε02n3h3mZ2e4
∴ T∝n3
∴ 1frequency (f) ∝n3
or f∝n-3

Topic: Physics, Atomic Physics, NEET
The orbital velocity of an artificial satellite in a circular orbit just above the earth's surface is v . For a satellite orbiting at an altitude of half of the earth's radius, the orbital velocity is

Options:
A 32v
B 32v
C 23v
D 23v

The correct answer is:
23v

Solution:
We know that v0=GMR for a satellite at at altitude R2 ,
v1=GMR+R2
therefore v1v=23

Topic: Physics, Gravitation, NEET
The 'Order' for the group of families Felidae and Canidae is ____(i)____ while Convolvulaceae and Solanaceae come under the order _____(ii)_____

Options:
A (i) - Primata, (ii) - Poales
B (i) - Carnivora, (ii) - Polymonials
C (i) - Mammalia, (ii) - Dicotyledonae
D (i) - Chordata, (ii) - Angiospermae

The correct answer is:
(i) - Carnivora, (ii) - Polymonials

Solution:
Felidae comprises the cats and Canidae includes the dogs. These two family ranks come under the same order carnivore as both of these are predatory and carnivore. Based on the floral patterns and characteristics, family groups Solanaceae and Convolvulaceae have the same order. The order rank is Polymonials.

Topic: Biology, The Living World, NEET
The order of a colligative property for 0.1M solution of the following is

Options:
A NaCl>Na2SO4>Na3PO4
B NaCl<Na2SO4<Na3PO4
C NaCl>Na2SO4≈Na3PO4
D NaCl<Na2SO4=Na3PO4

The correct answer is:
NaCl<Na2SO4<Na3PO4

Solution:
Colligative property in decreasing order
Na3PO4>Na2SO4>NaCl
Na3PO4→3Na++PO43-=4
Na2SO4→2Na++SO42-=3
NaCl→Na++Cl-=2

Topic: Chemistry, Solutions, NEET
The order of covalent character of KF, KI, KCI is

Options:
A KCl<KF<KI
B KI<KCl<KF
C KF<KI<KCl
D KF<KCl<KI

The correct answer is:
KF<KCl<KI

Solution:
As the size of anion size increases the ploarisability increases hence covalent character increases (As per Fajan's rules)
order of covalent character is KF<KCl<KI

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
The order of decreasing reactivity towards an electrophilic reagent, for the following would be:
(i) benzene
(ii) toluene
(iii) chlorobenzene
(iv) phenol

Options:
A (ii) $>$ (iv) $>$ (i) $>$ (iii)
B (iv) $>$ (iii) $>$ (ii) $>$ (i)
C (iv) $>$ (ii) $>$ (i) $>$ (iii)
D (i) $>$ (ii) $>$ (iii) $>$ (iv)

The correct answer is:
(iv) $>$ (ii) $>$ (i) $>$ (iii)

Solution:
Electrophiles have high affinity for electrons. They attack at the site where electron-density is highest. Electron withdrawing substances increases the electron density. The electron withdrawing tendency decreases in the order :
$-\mathrm{OH}>-\mathrm{CH}_3>-\mathrm{H}>-\mathrm{Cl}$
Therefore, the correct order of reactivity towards electrophile is
$\mathrm{C}_6 \mathrm{H}_5 \mathrm{OH}>\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_3>\mathrm{C}_6 \mathrm{H}_6>\mathrm{C}_6 \mathrm{H}_5 \mathrm{Cl}$
Related Theory
Electrophilic substitution reaction in haloarenes occur slowly because halogen has a negative inductive effect, it decreases the electron density on the benzene ring due to resonance.

Topic: Chemistry, Hydrocarbons, NEET, NEET 2007
The order of energy absorbed which is responsible for the color of complexes

(A) NiH2O2(en)22+

(B) NiH2O4(en)2+ and

(C) Ni(en)32+ is

Options:
A (C)>(B)>(A)
B (C)>(A)>(B)
C (B)>(A)>(C)
D (A)>(B)>(C)

The correct answer is:
(C)>(A)>(B)

Solution:
The complexes with strong filed ligands absorbs the highest energy light than complexes with weak field ligands.

Ethylene diamine(en) is strong field ligand and H2O is the weak field ligand.

Hence, the correct order of energy absorbed is

Nien32+>NiH2O2en22+>NiH2O4en2+

Topic: Chemistry, Coordination Compounds, NEET, NEET 2022 (Phase 1)
The order of given reaction H2+Cl2âSun light2HCl is

Options:
A 1
B 2
C 3
D 0

The correct answer is:
0

Solution:
The rate of this photochemical reaction is independent of the concentration. Therefore, it is zero order reaction.

Topic: Chemistry, Chemical Kinetics, NEET
The order of increasing reactivity of the following compounds towards HCl will be
1 CH2=CH2
(2) (CH3)2C=CH2
3 CH3CH=CHCH3

Options:
A 1<2<3
B 1<3<2
C 3<2<1
D 2<1<3

The correct answer is:
1<3<2

Solution:
Reactivity of alkene towards electrophilic addition depends upon nature of electron rich double bond and stability of carbocation formed.

Topic: Chemistry, Hydrocarbons, NEET
The order of increasing sizes of atomic radii among the elements O, S, Se and As is :

Options:
A As < S < O < Se
B Se < S < As < O
C O < S < As < Se
D O < S < Se < As

The correct answer is:
O < S < Se < As

Solution:
On moving down in a group atomic radius increases due to successive addition of extra shell hence
O < S < Se
Further As is in group 15 having one less electron in its p orbital hence have higher atomic radii than group 16 elements.
i.e., O < S < Se < As

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
The order of ionic conductance of alkali metal ions in their aquous solution in a given concentration is

Options:
A Li+<Na+<K+<Rb+
B Li+>Na+>K+>Rb+
C Li+<Na+>K+>Rb+
D Li+=Na+<K+<Rb+

The correct answer is:
Li+<Na+<K+<Rb+

Solution:
The smaller cation have higher charge and greater extent of hydration, thus lesser will be ionic conductance and mobility. With the increase in size of cation the size of the hydrated ion decreases, hence ionic conductance increases.

Topic: Chemistry, s Block Elements, NEET
The order of leaving group ability in the following groups is
−OAc    I    −OMe   II    − OSO 2 Me   III    − OSO 2 CF 3   IV

Options:
A I>II>III>IV
B IV>III>I>II
C III>II>I>IV
D II>III>IV>I

The correct answer is:
IV>III>I>II

Solution:
The conjugate base of strong acids are weak, and weak conjugate bases are good leaving groups IV>III>I>II .

Topic: Chemistry, General Organic Chemistry, NEET