JEE Main Previous Year Papers Questions of Chemistry With Solutions are available at eSaral.
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Previous Years AIEEE/JEE Mains Questions
Q. The bond dissociation energy of B–F in $\mathrm{BF}_{3}$ is 646 kJ $\mathrm{mol}^{-1}$whereas that of C–F in $\mathrm{CF}_{4}$ is 515 kJ mol–1. The correct reason for higher B–F bond dissociation energy as compared to that of C–F is :-
(1) Significant $\mathrm{p} \pi-\mathrm{p} \pi$ interaction between B and F in $\mathrm{BF}_{3}$whereas there is not possibility of such interaction between C and F in $\mathrm{CF}_{4}$.
(2) Lower degree of p – p interaction between B and F in $\mathrm{BF}_{3}$ than that
between C and F in $\mathrm{CF}_{4}$
(3)Smaller size of B-atom as compared to that of C-atom
(4) Stronger bond between B and F in $\mathrm{BF}_{3}$ as compared to that between C and F in $\mathrm{CF}_{4}$
[AIEEE-2009]
Ans. (1)
Due to back bonding in BF3 molecule all B–F bond having partial double bond character.
Q. Using MO theory predict which of the following species has the shortest bond length ?
(1) $\mathrm{o}_{2}^{-}$
(2) $\mathrm{O}_{2}^{2-}$
(3) $\mathrm{O}_{2}^{2+}$
(4) $\mathrm{O}_{2}^{+}$
[AIEEE-2009]
Ans. (3)
Q. The hybridisation of orbitals of N atom in $\mathrm{NO}_{3}^{-}, \mathrm{NO}_{2}^{+}$ and $\mathrm{NH}_{4}^{+}$ are respectively:-
[AIEEE-2011]
Ans. (4)
Q. The structure of $\mathrm{IF}_{7}$ is :-
(1) octahedral
(2) pentagonal bipyramid
(3) square pyramid
(4) trigonal bipyramid
[AIEEE-2011]
Ans. (2)
Q. Among the following the maximum covalent character is shown by the compound :-
(1) $\mathrm{AlCl}_{3}$
(2) $\mathrm{MgCl}_{2}$
(3) FeCl $_{2}$
(4) $\mathrm{SnCl}_{2}$
[AIEEE-2011]
Ans. (1)
$\mathrm{Al}^{+3}$ having highest polarizing power than other : having greater covalent character
Q. Which of the following has maximum number of lone pairs associated with Xe
(1) $\mathrm{XeO}_{3}$
(2) $\mathrm{XeF}_{4}$
(3) XeF $_{6}$
(4) $\mathrm{XeF}_{2}$
[AIEEE-2011]
Ans. (4)
Q. The number of types of bonds between two carbon atoms in calcium carbide is :-
(1) One sigma, two pi
(2) One sigma, one pi
(3) Two sigma, one pi
(4) Two sigma, two pi
[AIEEE-2011]
Ans. (1)
$\mathrm{Ca}^{+2}(\mathrm{C} \equiv \mathrm{C})^{2-}$
Q. The molecule having smallest bond angle is :-
(1) $\mathrm{PCl}_{3}$
(2) $\mathrm{NCl}_{3}$
(4) $\mathrm{SbCl}_{3}$
[AIEEE-2012]
(4) $\mathrm{SbCl}_{3}$
[AIEEE-2012]
Ans. (4)
Bond angle order $\mathrm{NCl}_{3}>\mathrm{PCl}_{3}>\mathrm{AsCl}_{3}>\mathrm{SbCl}_{3}$
Q. In which of the following pairs the two species are not isostructural ?
(1) $\mathrm{AIF}_{6}^{3-}$ and $\mathrm{SF}_{6}$
(3) $\mathrm{CO}_{3}^{2-}$ and $\mathrm{NO}_{3}^{-}$
(3) $\mathrm{PCl}_{4}^{+}$ and $\mathrm{SiCl}_{4}$
(4) $\mathrm{PF}_{5}$ and $\mathrm{BrF}_{5}$
[AIEEE-2012]
Ans. (4)
Q. The number of S–S bonds in $\mathrm{SO}_{3}, \mathrm{S}_{2} \mathrm{O}_{3}^{2-}, \mathrm{S}_{2} \mathrm{O}_{6}^{2-}$ and $\mathrm{S}_{2} \mathrm{O}_{8}^{2-}$ respectively are :-
(1) 1, 0, 1, 0 (2) 0, 1, 1, 0 (3) 1, 0, 0, 1 (4) 0, 1, 0, 1
[JEE-MAINS(Online) 2012]
Ans. (2)
Q. Dipole moment is shown by :-
(1) trans-2, 3-dichloro- 2-butene
(2) 1, 2-dichlorobenzene
(3) 1, 4-dichlorobenzene
(4) trans-1, 2-dinitroethene
[JEE-MAINS(Online) 2012]
Ans. (2)
Q. Among the following species which two have trigonal bipyramidal shape ?
[JEE-MAINS(Online) 2012]
[JEE-MAINS(Online) 2012]
Ans. (Bonus)
Q. Among the following, the species having the smallest bond is :-
(1) NO
(2) $\mathrm{NO}^{+}$
(3) $\mathrm{O}_{2}$
(4) $\mathrm{NO}^{-}$
[JEE-MAINS(Online) 2012]
Ans. (2)
Q. Based on lattice energy and other considerations, which one of the following alkali metal chloride is expected to have the highest melting point ?
(1) RbCl
(2) LiCl
(3) KCl
(4) NaCl
[JEE-MAINS(Online) 2012]
Ans. (4)
Highest melting is of NaCl
Q. Which of the following has the square planar structure :-
(1) $\mathrm{NH}_{4}^{+}$
(2) $\mathrm{CCl}_{4}$
(3) $\mathrm{XeF}_{4}$
(4) $\mathrm{BF}_{4}^{-}$
[JEE-MAINS(Online) 2012]
Ans. (3)
Hybridisation $\mathrm{Sp}^{3} \mathrm{d}^{2}$
Shape – square planar
Hybridisation $\mathrm{Sp}^{3} \mathrm{d}^{2}$
Shape – square planar
Q. The compound of Xenon with zero dipole moment is :-
(1) $\mathrm{XeO}_{3}$
(2) $\mathrm{XeO}_{2}$
(3) $\mathrm{XeF}_{4}$
(4) $\mathrm{XeOF}_{4}$
[JEE-MAINS(Online) 2012]
Ans. (3)
Q. Among the following the molecule with the lowest dipole moment is :-
(1) $\mathrm{CHCl}_{3}$
(2) $\mathrm{CH}_{2} \mathrm{Cl}_{2}$
(3) $\mathrm{CCl}_{4}$
(4) $\mathrm{CH}_{3} \mathrm{Cl}$
[JEE-MAINS(Online) 2012]
Ans. (3)
$\mathrm{CCl}_{4}<\mathrm{CHCl}_{3}<\mathrm{CH}_{2} \mathrm{Cl}_{2}<\mathrm{CH}_{3} \mathrm{Cl}(\text { Dipolar moment })$
Q. The formation of molecular complex $\mathrm{BF}_{3}-\mathrm{NH}_{3}$ results in a change in hybridisation of boron
(1) from $\operatorname{sp}^{3}$ to $\mathrm{sp}^{3} \mathrm{d}$
(2) from $\operatorname{sp}^{2}$ to $\mathrm{dsp}^{2}$
(3) from $\operatorname{sp}^{3}$ to $\mathrm{sp}^{2}$
(4) from $\operatorname{sp}^{2}$ to $\mathrm{sp}^{3}$
[JEE-MAINS(Online) 2012]
Ans. (4)
Q. Among the following chloro-compound having the lowest dipole moment is :-
(1) $\mathrm{CH}_{2} \mathrm{Cl}_{2}$
(2) $\mathrm{CH}_{3} \mathrm{Cl}$
(3) 
(4) 
(4)
Ans. (1)
$\mathrm{CH}_{2} \mathrm{Cl}_{2}$ has lowest dipole moment
Q. Which one of the following molecules is expected to exhibit diamagnetic behaviour ?
(1) $\mathrm{C}_{2}$
(2) $\mathrm{N}_{2}$
(3) $\mathrm{O}_{2}$
(4) $\mathrm{S}_{2}$
[AIEEE-2013]
Ans. (2)
$\mathrm{N}_{2}$ is diamagnetic
Q. Which of the following is the wrong statement?
(1) ONCl and $\mathrm{ONO}^{-}$ are not isoelectronic
(2) $\mathrm{O}_{3}$ molecule is bent
(3) Ozone is violet-black in solid state
(4) Ozone is diamagnetic gas
[JEE-maIN 2013]
Ans. (1)
Number of electron in ONCl an $\mathrm{ONO}^{-}$ is 32 & 24 respectively.
Q. In which of the following pairs of molecules/ions, both the species are not likely to exist ?
(1) $\mathrm{H}_{2}^{+}, \mathrm{He}_{2}^{2-}$
(2) $\mathrm{H}_{2}^{-}, \mathrm{He}_{2}^{2-}$
(3) $\mathrm{H}_{2}^{2+}, \mathrm{He}_{2}$
(4) $\mathrm{H}_{2}^{-}, \mathrm{H} \mathrm{e}_{2}^{2+}$
[JEE-main 2013]
Ans. (3)
Bond order of $\mathrm{H}_{2}^{2+} \& \mathrm{He}_{2}$ is zero i.e. these molecule do not exist.
Q. Stability of the species $\mathrm{Li}_{2}, \quad \mathrm{Li}_{2}^{-}$ and $\mathrm{Li}_{2}^{+}$ increases in the order of :-
(1) $\mathrm{Li}_{2}<\mathrm{Li}_{2}^{+}<\mathrm{Li}_{2}^{-}$
(2) $\mathrm{Li}_{2}^{-}<\mathrm{Li}_{2}^{+}<\mathrm{Li}_{2}$
(3) $\mathrm{Li}_{2}<\mathrm{Li}_{2}<\mathrm{Li}_{2}^{+}$
(4) $\mathrm{Li}_{2}^{-}<\mathrm{Li}_{2}<\mathrm{Li}_{2}^{+}$
[JEE-main 2013]
Ans. (2)
Q. Trigonal bipyramidal geometry is shown by:
(1) $\mathrm{XeO}_{3} \mathrm{F}_{2}$
(2) $\mathrm{XeOF}_{2}$
(3) $\left[\mathrm{XeF}_{8}\right]^{2-}$
[JEE-MAINS(Online) 2013]
[JEE-MAINS(Online) 2013]
Ans. (1)
Q. In which of the following ionization processes the bond energy has increased and also the magnetic behaviour has changed from paramagnetic to diamagnetic ?
(1) $\mathrm{NO} \rightarrow \mathrm{NO}^{+}$
(2) $\mathrm{O}_{2} \rightarrow \mathrm{O}_{2}^{+}$
(3) $\mathrm{N}_{2} \rightarrow \mathrm{N}_{2}^{+}$
( 4) $\mathrm{C}_{2} \rightarrow \mathrm{C}_{2}^{+}$
[JEE-MAINS(Online) 2013]
Ans. (1)
Q. Which one of the following molecules is polar?
(1) $\mathrm{CF}_{4}$
(2) $\mathrm{SbF}_{5}$
(3) $\mathrm{IF}_{5}$
(4) $\mathrm{XeF}_{4}$
[JEE-MAINS(Online) 2013]
Ans. (3)
Q. Oxidation state of sulphur in anions $\mathrm{SO}_{3,}^{2-} \mathrm{S}_{2} \mathrm{O}_{4}^{2-}$ and $\mathrm{S}_{2} \mathrm{O}_{6}^{2-}$ increases in the orders :
(1) $\mathrm{S}_{2} \mathrm{O}_{6}^{2-}<\mathrm{S}_{2} \mathrm{O}_{4}^{2-}<\mathrm{SO}_{3}^{2-}$
(2) $\mathrm{SO}_{3}^{2-}<\mathrm{S}_{2} \mathrm{O}_{4}^{2-}<\mathrm{S}_{2} \mathrm{O}_{6}^{2-}$
(3) $\mathrm{S}_{2} \mathrm{O}_{4}^{2-}<\mathrm{SO}_{3}^{2-}<\mathrm{S}_{2} \mathrm{O}_{6}^{2-}$
(4) $\mathrm{S}_{2} \mathrm{O}_{4}^{2-}<\mathrm{S}_{2} \mathrm{O}_{6}^{2-}<\mathrm{SO}_{3}^{2-}$
[JEE-MAINS(Online) 2013]
Ans. (3)
Q. Bond order normally gives idea of stability of a molecular species. All the molecules viz. $\mathrm{H}_{2}, \mathrm{Li}_{2}$ and $\mathrm{B}_{2}$ have the same bond order yet they are not equally stable. Their stability order is:
(1) $\mathrm{Li}_{2}>\mathrm{H}_{2}>\mathrm{B}_{2}$
(2) $\mathrm{H}_{2}>\mathrm{B}_{2}>\mathrm{Li}_{2}$
(3) $\mathrm{B}_{2}>\mathrm{H}_{2}>\mathrm{Li}_{2}$
(4) $\mathrm{Li}_{2}>\mathrm{B}_{2}>\mathrm{H}_{2}$
[JEE-MAINS(Online) 2013]
Ans. (2)
Q. The solubility order for alkali metal fluoride in water is :
(1) $\mathrm{LiF}<\mathrm{NaF}<\mathrm{KF}<\mathrm{RbF}$
(2) $\mathrm{LiF}>\mathrm{NaF}>\mathrm{KF}>\mathrm{RbF}$
(3) $\mathrm{RbF}<\mathrm{KF}<\mathrm{NaF}<\mathrm{LiF}$
(4) $\mathrm{LiF}<\mathrm{RbF}<\mathrm{KF}<\mathrm{NaF}$
[JEE-MAINS(Online) 2013]
Ans. (1)
Solubility order
LiF < NaF < KF < RbF
Q. $\mathrm{XeO}_{4}$ molecule is tetrahedral having :
(1) Two p $\pi$ -d $\pi$ bonds
(2) Four p $\pi$ - d $\pi$ bonds
(3) One $\mathrm{p} \pi-\mathrm{d} \pi$ bond
(4) Three p $\pi$ -d $\pi$ bonds
[JEE-MAINS(Online) 2013]
Ans. (2)
Q. Bond distance in HF is 9.17 × $10^{-11}$ m. Dipole moment of HF is 6.104 × 10–30 Cm.
The percent ionic character in HF will be : (electron charge = 1.60 × $10^{-19}$ C)
(1) 61.0%
(2) 38.0%
(3) 35.5%
(4) 41.5%
[JEE-MAINS(Online) 2013]
Ans. (4)
Q. The shape of $\mathrm{IF}_{6}^{-}$ is :
(1) Trigonally distorted octahedron
(2) Pyramidal
(3) Octahedral
(4) Square antiprism
[JEE-MAINS(Online) 2013]
Ans. (1)
Q. Which has trigonal bipyramidal shape ?
(1) $\mathrm{XeOF}_{4}$
(2) $\mathrm{XeO}_{3}$
(3) $\mathrm{XeO}_{3} \mathrm{F}_{2}$
(4) $\mathrm{XeOF}_{2}$
[JEE-MAINS(Online) 2013]
Ans. (3)
Q. The catenation tendency of C, Si and Ge is in the order Ge < Si < C. The bond energies
(in kJ $\mathrm{mol}^{-1}$) of C — C, Si —Si and Ge—Ge bonds are respectively :
(1) 348, 260, 297
(2) 348, 297, 260
(3) 297, 348, 260
(4) 260, 297, 348
[JEE-MAINS(Online) 2013]
Ans. (2)
Catenation/Bond energy order
C – C > Si – Si > Ge – Ge
Q. In which of the following sets, all the given species are isostructural ?
(1) $\mathrm{BF}_{3}, \mathrm{NF}_{3}, \mathrm{PF}_{3}, \mathrm{AlF}_{3}$
(2) $\mathrm{PCl}_{3}, \mathrm{AlCl}_{3}, \mathrm{BCl}_{3}, \mathrm{SbCl}_{3}$
(3) $\mathrm{BF}_{4}^{-}, \mathrm{CCl}_{4}, \mathrm{NH}_{4}^{+}, \mathrm{PCl}_{4}^{+}$
(4) $\mathrm{CO}_{2}, \mathrm{NO}_{2}, \mathrm{ClO}_{2}, \mathrm{SiO}_{2}$
[JEE-MAINS(Online) 2013]
Ans. (3)
$\mathrm{BF}_{4}^{-}, \mathrm{CC}_{4}, \mathrm{NH}_{4}^{+}, \mathrm{PCl}_{4}^{+}$ are terahedral
Q. The internuclear distances in O —O bonds for O, $\mathrm{O}_{2}, \mathrm{O}^{-}$2 and O respectively are :
(1) 1.49 Å, 1.21 Å, 1.12 Å, 1.30 Å
(2) 1.30 Å, 1.49 Å, 1.12 Å, 1.21
(3) 1.12 Å, 1.21 Å, 1.30 Å, 1.49 Å
(4) 1.21 Å, 1.12 Å, 1.49 Å, 1.30 Å
[JEE-MAINS(Online) 2013]
Ans. (3)
Q. Which one of the following properties is not shown by NO ?
(1) It combines with oxygen to form nitrogen dioxide
(2) It's bond order is 2.5
(3) It is diamagnetic in gaseous state
(4) It is a neutral oxide
[JEE-main 2014]
Ans. (3)
Q. For which of the following molecule significant $\mu \neq 0$
[JEE-main 2014]
[JEE-main 2014]
Ans. (2)
Q. The number and type of bonds in $\mathrm{C}_{2}^{2-} \mathrm{ion}$ in $\mathrm{CaC}_{2}$ are:
(1) Two $\sigma$ bonds and one $\pi-$ bond
(2) Two $\sigma$ bonds and two $\pi-$ bonds
(3) One $\sigma$ bond and two $\pi-$ bonds
(4) One $\sigma$ bond and one $\pi-$ bond
[JEE-MAINS(Online) 2014]
Ans. (3)
Q. For the compounds $\mathrm{CH}_{3} \mathrm{Cl}, \mathrm{CH}_{3} \mathrm{Br}, \mathrm{CH}_{3} \mathrm{I}$ and $\mathrm{CH}_{3} \mathrm{F}$
(1) $\mathrm{CH}_{3} \mathrm{F}<\mathrm{CH}_{3} \mathrm{Br}<\mathrm{CH}_{3} \mathrm{Cl}<\mathrm{CH}_{3} \mathrm{I}$
(2) $\mathrm{CH}_{3} \mathrm{F}<\mathrm{CH}_{3} \mathrm{Cl}<\mathrm{CH}_{3} \mathrm{Br}<\mathrm{CH}_{3} \mathrm{I}$
(3) $\mathrm{CH}_{3} \mathrm{Cl}<\mathrm{CH}_{3} \mathrm{Br}<\mathrm{CH}_{3} \mathrm{F}<\mathrm{CH}_{3} \mathrm{I}$, the correct order of increasing C-halogen bond length is :
(4) $\mathrm{CH}_{3} \mathrm{F}<\mathrm{CH}_{3} \mathrm{I}<\mathrm{CH}_{3} \mathrm{Br}<\mathrm{CH}_{3} \mathrm{Cl}$
[JEE-MAINS(Online) 2014]
Ans. (2)
Q. Which of the following has unpaired electron(s) ?
(1) $\mathrm{O}_{2}^{-}$
(2) $\mathrm{N}_{2}^{2+}$
(3) $\mathrm{O}_{2}^{2-}$
(4) $\mathrm{N}_{2}$
[JEE-MAINS(Online) 2014]
Ans. (1)
$\mathrm{O}_{2}^{-}$ ha one unpaired electron
Q. In allene $\left(\mathrm{C}_{3} \mathrm{H}_{4}\right)$, the type(s) of hybridization of the carbon atoms is (are):
(1) only sp $^{2}$
(2) $\mathrm{sp}^{2}$ and $\mathrm{sp}$
(3) sp and sp $^{3}$
(4) $\mathrm{sp}^{2}$ and $\mathrm{sp}^{3}$
[JEE-MAINS(Online) 2014]
Ans. (2)
Q. Shapes of certain interhalogen compounds are stated below. Which one of them is not correctly stated?
(1) IF $_{7}:$ Pentagonal bipyramid
(2) BrF $_{5}:$ Trigonal bipyramid
(4) $\mathrm{BrF}_{3}:$ Planar T-shaped
[JEE-MAINS(Online) 2014]
(4) $\mathrm{BrF}_{3}:$ Planar T-shaped
[JEE-MAINS(Online) 2014]
Ans. (2)
$\mathrm{BrF}_{5}$ have square pyramidal shape.
Q. The correct order of bond dissociation energy among $\mathrm{N}_{2}, \mathrm{O}_{2}, \mathrm{o}_{2}^{-}$ is shown in which of the following arrangements?
(1) $\mathrm{N}_{2}>\mathrm{O}_{2}>\mathrm{O}_{2}^{-}$
(2) $\mathrm{O}_{2}>\mathrm{O}_{2}^{-}>\mathrm{N}_{2}$
(3) $\mathrm{N}_{2}>\mathrm{O}_{2}^{-}>\mathrm{O}_{2}$
(4) $\mathrm{O}_{2}^{-}>\mathrm{O}_{2}>\mathrm{N}_{2}$
[JEE-MAINS(Online) 2014]
Ans. (1)
Q. Which of the following molecules has two sigma$(\sigma)$ and two $\operatorname{pi}(\pi)$ bonds :-
(1) HCN
(2) $\mathrm{C}_{2} \mathrm{H}_{2} \mathrm{Cl}_{2}$
(3) $\mathrm{N}_{2} \mathrm{F}_{2}$
(4) $\mathrm{C}_{2} \mathrm{H}_{4}$
[JEE-MAINS(Online) 2014]
Ans. (1)
Q. Which one of the following molecules is paramagnetic?
(1) NO
( 2) $\mathrm{O}_{3}$
(3) $\mathrm{N}_{2}$
(4) CO
[JEE-MAINS(Online) 2014]
Ans. (1)
NO has unpaired e $^{-} \therefore$ paramagnetic is nature
Q. Amongst LiCl, RbCl, $\mathrm{BeCl}_{2}$ and $\mathrm{MgCl}_{2}$ the compounds with the greatest and the least ionic character, respectively are :
(1) $\mathrm{RbCl}$ and $\mathrm{MgCl}_{2}$
(2) LiCl and RbCl
(3) $\mathrm{MgCl}_{2}$ and $\mathrm{BeCl}_{2}$
(4) $\mathrm{RbCl}$ and $\mathrm{BeCl}_{2}$
[JEE-MAINS(Online) 2014]
Ans. (4)
RbCl has highest ionic & and $\mathrm{BeCl}_{2}$ is most covalent
Q. The species in which the N atom is in a state of sp hybridization is :-
(1) $\mathrm{NO}_{2}$
(2) $\mathrm{NO}_{2}^{+}$
(3) $\mathrm{NO}_{2}^{-}$
(4) $\mathrm{NO}_{3}^{-}$
[JEE-MAINS 2016]
Ans. (2)
Q. Which of the following species is not paramagnetic :-
(1)NO
(2) CO
(3) $\mathrm{O}_{2}$
(4) $\mathrm{B}_{2}$
[JEE-MAINS 2017]
Ans. (2)
Q. Total number of lone pair of electrons in $\mathrm{I}_{3}^{-} \mathrm{ion}$ is
(1) 6 (2) 9 (3) 12 (4) 3
[JEE-MAINS 2018]
Ans. (2)
Q. According to molecular orbital theory, which of the following will not be a viable molecule ?
(1) $\mathrm{He}_{2}^{+}$
(2) $\mathrm{H}_{2}^{-}$
(3) $\mathrm{H}_{2}^{2-}$
(4) $\mathrm{He}_{2}^{2+}$
[JEE-MAINS 2018]
Ans. (3)
Q. Which of the following compounds contain(s) no covalent bond(s) ?
$\mathrm{KCl}, \mathrm{PH}_{3}, \mathrm{O}_{2}, \mathrm{B}_{2} \mathrm{H}_{6}, \mathrm{H}_{2} \mathrm{SO}_{4}$
$(1) \mathrm{KCl}, \mathrm{H}_{2} \mathrm{SO}_{4}$
(2) KC1
(3) $\mathrm{KCl}, \mathrm{B}_{2} \mathrm{H}_{6}$
(4) $\mathrm{KCl}, \mathrm{B}_{2} \mathrm{H}_{6}, \mathrm{PH}_{3}$
[JEE-MAINS 2018]
Ans. (2)
Comments
Alakh Pandey ( Physics wallah)
April 29, 2021, 6:24 p.m.
Are madharchodo randio ke aulaad gaaaaaaaaaaaaar far ke bajaaaaaaaar ke le leeeengeeee
Karthik
Feb. 18, 2021, 5:05 p.m.
Chemical bonding is so difficult to remember structures
And I want some structure
P shree mohan chandra naik
Feb. 16, 2021, 3:41 p.m.
it saved my time a lot thank you so much it really helped me a lot