UNIT#10 CHEMICAL BONDING Flashcards
Which of the following has largest ionic size?
N-3
In a period, the atomic radii:
Decrease
Which of the following is correct realtion for atmoic radius:
A->A>A+
Ionization energy depends upon:
➡Atomic/Ionic Radii
➡Nature of orbital
➡Shielding effect
Which of the following has highest ionization energy value:
He
(I.E direclty proportional Stabilitiy of electronic configuration)
Greater shielding effect corresponds to -__ ionization energy value
Lesser
The group that has maximum 1st ionization energy values:
ns^2, np^6
(Octet is complete)
Which of the following group has maximum 1st electron affinity value in same period?
VII A
Which of the following element has lowest electron affinity?
He
(E.A inverseily proportional to stability of electronic configuration)
An ionic compound A+B- is most likely to form when:
➡Ionization energy of A is Low
➡Electron affinity of B is high
Formation of ionic bond is favoured by:
Low Ionization Energy of metal
Maximum ionic character is exhibited by:
CsF
(E.N difference of 3.3)
All of the following species have dative bond except:
OH-
Co-oridinate covalent bond is present in;
Hydronium Ion
The percentage of co-ordinate covalent bond present in BF4- and NH4- respectively:
25% each
If the sharing of an electron pair is unequal and the atom have an electronegativity difference of 1.4 to 1.6, what is this type of sharing called:
Polar Covalent
The following molecules has linear structure except:
SO2
Which of the following species has lone pair of electrons on central atom?
PCl3
Which pair has trigonal planar geometry?
➡BF3
➡AlH3
The shape of NH2- is:
Angular
WHich molecular gemoetry is not possible for AB4 type molecules
Trigonal Planar
The correct orer of bond angles is represented in:
CH4 >H2O> NF3>H2S
Which of the following has perect triangular structure:
SO3
(AB3 type)
Limitation to valence bond theory (VBT) is that:
It doesn’t explain paramagnetic behavior of O2
End to end overlapping of orbitals give rise to the formation of:
Sigma Bond
Pi bonds are formed by overlapping of:
Un-Hybrid Orbital
The concept of hybridization was given to remove which of the following drawbacks of V.B.T?
It could not explain tetravalency of carbon
Cl2 molecule is formed by the overlap of:
p-p head on overlapping of orbitals
The process in which the orbitals of different energies and shape mix with each other to give equivalent orbitals is called:
Hybridization
In which of the following species central metal atom is not sp3 hybridized:
NO3-
In ground state the unpaired electrons in carbon are:
2
The central atom which may not follow the octet rule while forming covalent bond
P
Which one shows high %age of the ionic character
HF
(Directly related to electronegativity difference)
Dipole moment gives the information about:
➡%ionic character
➡Bond angles
➡Geometry of the molecule
Bond length depends upon:
➡Hybridization on central atom
➡Nature of molecule
➡Size of central atom
Choose the incorrect relationship of bond energies:
➡Br-Br > I-I❌
➡Cl-Cl > F-F❌
➡C-C > N-N (Triple Bond)✅
The S.I unit of dipole moment is:
mC
Which of the following moelcules has non-zero dipole moment.
CH3Cl
Maximum dipole moment is possessed by:
H2O
The experimentally determined bond legth of C-Cl is 176.7pm and C-C is 154 pm, what would be the radius o Cl atom:
99.7 pm
(Bond Length= rc + rcl)
All elements get thier stabilization to attain nearest configuration:
Noble Gases
The difference in the E.N values of the bonded atoms between two atoms is an index to ___ of covalent bond.
Polar Nature
p character in sp:
50%
Which bonds are present in moelcule of H2, according to VBT:
SIgma Bond
Due to ionic character, bond length:
Decreases
Which of the following bond has more energy:
Ionic
VBT proposed by:
L-Pauling
Hybridization in ethyne:
sp-sp
The geomerty of AB3 type molecule is:
Trigonal Planar
Number o unpaired electrons in CO+2 is:
3
Bond order of O2-2
1
The ionic radius is always _____ than the atomic radius from which it is derived:
Smaller
The valence electron pairs are arranged around the central atom to remain at maximum distance apart to keep repulsion:
Minimum
Geometry of AlCl3 is:
AB3
Which one is more electronegative:
F
All are AB2 type except:
SO3
Ionization energy is inversely proportional to:
➡Shielding Effect
➡Atomic size
Hybridziation of carbon in carbonyl group is:
sp2
Ionization energy depends on which of the following factors?
➡Size of atoms
➡Nuclear Charge
➡Number of shells
Angle in ammonia:
180
Bond length in alkyne:
1.34 A
Shape of H2S:
Angular
He follows:
Duplet Rule
Extened octet rule:
PCl5
The second ionization energy is maximum for:
Li
Valence shell electron pair repuslion theory is given as:
VSEPR
SnCl2 is an example of:
AB3
Which of the following has least bond energy
I2
VSEPR explains the:
Shape of molecules
Bond angle in water:
104.5 Degree
The ionization energy increases from left to right in a period due to increase in:
➡Nuclear Charge
➡Number of electrons
➡Atomic Number
Which of the following represent spin of two electrons in orbital:
+1/2, -1/2
The forces present within a molecule are called as:
Chemical Bonds
The moelcules like CH4, CCl4 or SiH4 show attitude of non-polarity due to:
Symmetry of structure
The electron affinity and atomic radius are ___ to each other:
Inversely Proportional
If a moelcule contains 4 electron apirs, The shape of molecule will be:
Tetrahedral
The unit of electron affinity is:
KJ/mol
According to VSEPR, the repulsive force between the electron pairs of central atom of a molecule are in the order:
Lone Pair-Lone Pair>Lone Pair-Bond Pair>Bond Pair-Bond Pair
What is the exact value of angle in BF3 :
120 Degree
Which option show all the molecules with bond angle 109.5 degree.
SiCl4, NH4+, CH4
The structure of Xenon Trioxide. With reference to the VSEPR theory, the shape of XeO3 is:
Trigonal Pyramidal
Which of the following sets constitutes of all the molecules and ions of non-polar geometry?
CH4, NH4+, MnO4-, NF3
The shape of CO2 moelcule is similar to;
BeF2
What is the shape of ammonia NH3 molecule?
Pyramidal
(AB3E)
The number of bonds in nitrogen molecule is:
One sigma and Two pi bonds
When the two partially filled atomic orbital overlap in such a way that the probability of finding the electron is maximum around the line joining the two nuclei, the result is the formation of:
Sigma Bond
pi-bond is formed by sideways overlap of:
p-orbital
The angle between un-hybridized p-orbital and three sp2 hybridized orbitals of each carbon atom is:
90 degree
Which of the following molecule has largest number of shared pair electrons?
C2H4
Which one of the following molecules has sp3 hybridization:
CH4
Which of the following molecule has zero dipole moment?
BF3
Which of the following has zero dipole moment:
BF3
Among the following molecules, which one has coordinate covalent (dative) bond?
CO
Which of the following molecule has zero dipole moment?
BF3
For formation of ionic bond, electronegativity difference should be:
More than 1.7
The ionization energy of hydrogen atom is:
1313kJ/mole
The elements for which the value of ionization energy is low can:
Lose electron readily
Electron affinity of the atom is the energy released when:
Electron is added to gaseous atom
The shielding effect of inner electron is responsible for:
Decreasing ionization energy
What will be the shape of a molecule which contains two sigma bond pairs and one lone pair?
V shape
A molecule which contains two lone pairs and two bond pairs of electrons in valence shell of central atom, geometrical shape of molecules will be:
Angular
Fe+2 will from the most ionic bond with:
F-1
(Metallinc cation combines with most electronegative atom like F-1 to form most ionic bond)
Which of the following elements has lowest first ionization energy?
B
Which one of the following elements has the largest second ionization energy?
F
The bond angle in H2S is less than H2O, it is due to:
The small size of the oxygen atom
In the second period of elements, although oxygen lies next to nitrogen yet its first ionization energy is lower than that of nitrogen because:
In oxygen, there exists repulsion between pair of electrons present in the same orbital of valence shell
Which of the following has the highest value of electronegativity?
F
Which of the following hybrid orbital have maximum s-character?
sp
The first ionization energy is maximum for:
Mg
Which of the following has largest ionic size:
N-³
(Greater the negative charge, greater the size of ion)
Which of the following is correct relation for atomic radius:
A- > A > A+
For which molecule the bonding pair of electrons is equally shared between the atoms?
H2
An element with highest first ionization energy?
Nitrogen
Which factor does not effect ionization energy across the period:
Number of shell
Elements with ____ first ionization energies and ____ electron affinities generally form cations:
➡Low
➡Positive or Slightly Negative
Which pair of species have electronic configuration ends on 2s2 2p6 in their highest occupied energy level.
➡Na+
➡O-2
Which of the following have their outer most shell complete in atomic form:
Noble Gases
An atom loses or gains electrons, to:
➡Gain stability
➡Form a bond
➡Complete its outermost shell
Which of the following compounds does not obey octet rule:
➡PF3❌
➡BF3✅
➡NF3❌
➡AsF3❌
The compound which have three types of bonds is:
NH4Cl
A compound which is most ionic in nature:
RbF
(Due to High electonegativity difference)
Which of the following solid does not contain covalent bond:
Copper
Structure of AlCl3:
Triangular structure
Structure of NH3, PH3, H3O+:
Trigonal Pyramidal
Which have bond angle of 120°?
➡BF3
➡AlCl3
➡C2H4
NH3 has bond angle:
107.5°
Structure of ammonia is:
Pyramidal
In NH3 and NF3 molecules the bond angle is;
NH3 > NF3
(Due to attachment of more electronegative atoms)
Which type of bond is formed by overlap of p-orbitals perpendicular to the two nuclei:
Pi(π) bond
Hybridization is the extended form of ___ theory.
Valence Bond
Pi(π) bond:
Decreases bond length
The percentage of s-character in hybrid orbital which indicates shortest bond length:
50% s-character
When water donates its electron pair to hydrogen ion to form hydronium ion, hybridization is changed from;
Remains unchanged
(In H2O sp3 and in H3O+ sp3)
The hybridization state of ‘S’ in SO3 similar to that of:
C in C2H4
Which of the following is the most stable element:
Nitrogen
(Nitrogen is the most stable element because its bond energy is higher)
Which one has highest average bond energy?
N≡N
(Due to smaller size and multiple bonds)
When bond order increases, then bond length becomes ____ and the bond becomes:
➡Shorter
➡Stronger
The bond energy of Cl-Cl bond is;
242 kJ/mol
Which one has dipole moment?
o-Dichlorobenzene
Ionic compounds do not show the phenomenon of isomerism because bonds are:
➡Non-Directional
➡Non-Rigid
Which among the following has net dipole moment?
S2Cl2
Which of the following statements is incorrect
➡Among halogens chlorine has maximum electron affinity❌
➡Along the period M.P and B.P increases upto IVA group❌
➡Among Be, B, C and N, the Be element has minimum ionization energy value✅
➡Cs is the most electropositive and F is the most electronegative element❌
Which order of first ionization energy is correct:
Al < Mg
First electron affinity is maximum for:
Chlorine
Which factor does not effect I.E. across the period
➡Number of shells
➡Shielding Effect
Which of following does not affect I.E in group:
Nature of orbital
Which group of periodic table shown generally abnormal trends of ionization energy?
➡IIIA
➡VIA
In general, ionization energy increases along the period. The group which show maximum ionization energy?
VIIIA
The valence shell is:
The highest energy level occupied by electrons
Which of the following has the least bond angle:
➡BCl3 = 120°
➡NH3 = 107.5°
➡H2O = 104.5°
➡CH4 = 109.5°
A compound which has all the three types of chemical bonds:
➡CuSO4 . 5H2O
➡NaBH4
➡NH4Cl
In which of the following can donate an electron pair to the central atom?
There is no lone pair in central atom of BF3, H3O+ and AlCl3
Which among the following bonds shows the maximum bond strength?
Sigma Bond
Correct statement when coordinate covalent bond is formed between NH3 and BF3:
Ammonia donates its lone pair to 2p orbital of Boron
Which of the following molecules contains maximum number of lone pairs:
Chlorine gas
A compound which is most ionic in nature:
RbF
(Due to high electronegativity difference)
Bonding in phosphonium ion is ____ percent covalent:
75
Which of the following molecules contains six bonding electrons:
NF3
%age of coordinate covalent bond in NH4+:
25%
Which one has lone pair with central atom:
H2O
The shape of NH2-¹:
Angular
All of the following pairs have same shapes except:
➡SO2
➡AlCl3
Bond angle in paraffins is:
109.5°
Which molecule is planar:
C2Cl4
Which one of the following has maximum bond angle:
CO2
Choose the species that is incorrectly matched with the shape of the central atom:
➡CF4 = Tetrahedral❌
➡BeCl2 = Linear❌
➡H2O = Tetrahedral✅
➡NH3 = Pyramidal❌
According to VSEPR theory, a moelcule with the general formula AX4 with one lone pair will have a _____ molecular shape.
Trigonal BiPyramidal
Total no. of sigma electrons in one molecule of C2H2:
6
The carbon number 2 in the structure CH2=CH-CH2-CH3 shows a type of hybridization:
sp2
In which of the followings central atom is not hybridized:
AlH3
In which of the following molecules central atom is not sp3 hybridized:
SnCl2
In which of the following compound, carbon atoms has sp2 hybridization only:
1,3-butadiene
Which are the species in which central atom undergoes sp3 hybridization?
(i) SnCl2
(ii) NF3
(iii) SO4 -²
(iv) H2S
Select the correct answer using the code given below:
➡ii
➡iii
➡iv
All the atoms are coplanar in the molecule:
BF3
Which hybrid orbitals are used for bonding in triangular pyramidal molecule:
sp3
In the resonance structure of benzene the number of σ-bonds and π delocalized electrons are respectively:
➡12
➡6
The hybridization associated with the central atom of a molecule in which all the bond angles are 120° is:
sp2
In NH3, the covalent bonds are formed by:
s-sp3 overlap
Which of the following has the largest carbon-carbon bond length:
C2H6
The order of bond strength as a result of following head to head overlapping is;
p-p > s-p > s-s
Strongest bond among the following is;
H-H
The molecule having highest bond energy is;
C ≡ O
Which of the following has minimum bond dissociation energy:
I2
Which of the following is the best explaination that CO2 is non-polar molecule:
Net Dipole moment is zero
____ has highest dipole moment.
CHCl3
Covalent compounds show the phenomenon of isomerism because covalent bonds are:
➡Directional
➡Rigid
A molecule which does not have zero dipole moment
CO
Which of the following is most polar?
CH3F
Which of the following compounds is non-polar?
CO2
Greater the dipole moment:
Greater is the ionic nature
NH3 has net dipole moment but BF3 has zero dipole moment becasue of;
➡NH3 is pyramidal
➡BF3 is trigonal planar
2nd ionization energy of Mg is higher than the first because:
The nuclear pull for Mg+1 electrons is more than that for the Mg atom
Arrange the following according to the correct trend of 1st ionization energies: Na, Mg, Al, P, S
Na < Al < Mg < S < P
The second electron affinity value is ways with a positive sign. It is due to the repulsion of second incoming electron with;
Anion
Which one of the following has maximum electron affinity:
Cl
The octet rule is followed by the central atom in;
CCl4
Orbital around a single nucleus is called:
Atomic orbital