Sigma Bond and Pi Bond
Trending Questions
Q.
What is the ratio of sigma and pi bonds in benzene?
Q. Choose the wrong statement according to the valence bond theory:
- A σ-bond is stronger than a π-bond
- p-orbitals always have only sideways overlapping
- s-orbitals never form π-bonds
- There can be only one sigma bond between two atoms
Q. In C4−3, the number of σ and π bonds are:
- 2 σ and 2 π bonds
- 3 σ and 1 π bonds
- 2 σ and 1 π bonds
- 2 σ and 3 π bonds
Q.
Can form bonds?
Q. A π-bond is formed by the overlap of:
- s−s orbitals
- s−p orbitals
- p−p orbitals in end to end manner
- p−p orbitals in sideways manner
Q. Which of the following statements is correct regarding the formation of a sigma bond?
- Sideways overlap of orbitals take place
- End to end overlap of orbitals take place
- Sideways as well as end to end overlap of orbitals take place
- None of the above
Q. Which type of overlapping results in the formation of a π bond?
- Axial overlapping of s-s orbitals
- Lateral overlapping of p-p orbitals
- Axial overlapping of p-p orbitals
- Axial overlapping of s-p orbitals
Q. Which of the following is correct regarding the enolic form of acetone?
- 8 σ and 2 π bonds
- 10 σ and 1 π bonds
- 9 σ and 2 π bonds
- 9 σ and 1 π bonds
Q. Choose the wrong statement according to the valence bond theory:
- A σ-bond is stronger than a π-bond
- p-orbitals always have only sideways overlapping
- s-orbitals never form π-bonds
- There can be only one sigma bond between two atoms
Q. The ratio of number of σ and π bonds in benzene is:
- 2
- 6
- 4
- 8
Q.
Among the following, the least stable resonance structure is:
Q. Calculate total number of valence electrons in CH3CH2Cl :
- 34
- 20
- 17
- 38
Q. In C4−3, the number of σ and π bonds are:
- 2 σ and 2 π bonds
- 3 σ and 1 π bonds
- 2 σ and 1 π bonds
- 2 σ and 3 π bonds
Q. Which one of the following statements is not correct for sigma- and pi-bonds formed between two carbon atoms?
- Sigma bond is stronger than a pi bond
- Bond energies of sigma- and pi-bonds are of the order of 265 kJ/mol and 346 kJ/mol, respectively
- Free rotation of atoms about a sigma-bond is allowed but not in case of a pi-bond
- Sigma-bond determines the direction between carbon atoms but a pi-bond has no effect in this regard
Q. Which of the following statements is correct regarding the formation of a sigma bond?
- Sideways overlap of orbitals take place
- End to end overlap of orbitals take place
- Sideways as well as end to end overlap of orbitals take place
- None of the above
Q. Assertion: Equal number of sigma and pi bonds are present in ethyne.
Reason: π-bond is stronger than sigma bond.
Reason: π-bond is stronger than sigma bond.
- The assertion and the reason are true and the reason is the correct explanation of the assertion
- The assertion and the reason are true but the reason is not the correct explanation of the assertion
- The assertion is true but the reason is false
- Both the assertion and the reason are false
Q. Which of the following species contain equal number of α and π− bonds?
- CH2(CN)2
- HCO−3
- XeO4
- (CN)2
Q. Identify a molecule which does not exist.
(NEET 2020)
(NEET 2020)
- C2
- O2
- He2
- Li2
Q. The enolic form of ethyl acetoacetate has:
- 9 sigma bonds and 1 pi bond
- 18 sigma bonds and 2 pi bonds
- 16 sigma bonds and 1 pi bond
- 9 sigma bonds and 2 pi bonds
Q. How many π bonds are present in acetophenone.
- 4
- 16
- 10
- 6
Q. Assertion: Equal number of sigma and pi bonds are present in ethyne.
Reason: π-bond is stronger than sigma bond.
Reason: π-bond is stronger than sigma bond.
- The assertion and the reason are true and the reason is the correct explanation of the assertion
- The assertion and the reason are true but the reason is not the correct explanation of the assertion
- The assertion is true but the reason is false
- Both the assertion and the reason are false
Q. The ratio of number of σ and π bonds in benzene is:
- 2
- 6
- 4
- 8
Q. Which of the following statements is correct for the sigma and the pi bonds formed between two carbon atoms?
- Free rotation of atoms about a sigma bond is allowed but not in the case of pi bond
- Sigma bond determines the direction between carbon atoms but a pi bond has no primary effect in this regard
- Sigma bond is stronger than a pi bond
- All of the above
Q. The number and type of bonds between two carbon atoms in calcium carbide are :
- One sigma, one pi
- One sigma, two pi
- Two sigma, one pi
- Two sigma, two pi
Q. The number of sp2−sp2 sigma bonds in the compound given below is:
- 1
- 3
- 4
- 5
Q. Which of the following statements are correct for the formation of a stable bond according to the valence bond theory?
- The electrons should have opposite spins
- The two atoms should be close to each other
- Higher overlapping of the electron clouds
- All are correct
Q. Which one of the following molecules is formed by p−p overlapping?
- Br2
- HBr
- H2O
- PH3
Q.
Among the following which species has same number of σ and π bonds.
C7H8
C2(CN)4
C2H4
C2H2
Q. The failure of VBT to explain the tetrahedral geomerty of CH4 is because:
- All the C−H bond distance and H−C−H bond angles are equal in CH4
- CH4 is ionic
- It contains coordinate covalent bond
- All of the above