ECAT Pre Engineering Chemistry Chapter 6 MCQ Test With Answer

In OF₂, number of bond pairs and Ione paris of electrons are respectively

• 2,6 A
• 2,8 B
• 2,10 C
• 2,9 D

One of the following bonds is polar but compound is non-polar

• H₂O A
• NH₃ B
• HCl C
• CO₂ D

Fluorine molecule is formed by

• The axial p-p overlap A
• The sidewise p-p overlap B
• The axial s-p overlap C
• The overlap of two sp²hybrid orbitals D

Which of the following species is paramagnetic?

• CO₂ A
• NO B
• O^2- C
• CN D

Atomic number of Al is 13. When it forms ionic bond with oxygen the number of electrons lost by 1 Al atom is

• 1 A
• 2 B
• 3 C
• 4 D

If two lone pairs are present then bond angle of tetrahedral compound reduces to ______ degrees

• 109.5° A
• 107.5° B
• 104.5° C
• None D

Nitrogen in NH₃is sp³hybridized but the bond angle in NH₃is 107° and not 109.5° due to

• sp³orbital planar A
• sp³orbital trigonal B
• Repulsion between lone pair and bonded pairs C
• None of them D

The nature of interparticle forces in benzene is

• Dipole-dipole interaction A
• Dispersion force B
• Ion-dipole interaction C
• H-bonding D

Two H-atom combine to form a strong H₂molecule due to

• Increase in potential energy A
• Decrease in potential energy B
• Energy remains unchanged C
• Distance is increased D

Shielding effect intervening electrons causes

• Decreases in atomic radii in a period from right to left A
• Increase in atomic radii in a period from left to righ t B
• Decrease in atomic radii down the group C
• Increase in atomic radii down the group D

The atomic radius of hydrogen is 37

• Pecometer A
• Manometer B
• Angstrom C
• Micrometer D

Hydrogen chloride molecule contains

• Covalent bond A
• Double bond B
• Co-ordinate bond C
• Electrovalent bond D

An ionic compound M₂S₃is formed by the metal M,, the metal is

• Ca A
• Ba B
• K C
• Al D

The number of bonds in nitrogen molecule is

• 
  A
• 
  B
• 
  C
• 
  D

When two hydrogen atoms approach to form a chemical bond

• The repulsive forces dominate the attractive forces A
• The attractive forces, dominate the repulsive forces B
• The energy of atoms increases C
• The two atoms start ionization D

The covalent bonds are

• Unidirectional A
• Bi-directional B
• Non-directional C
• Multi-directional D

From the difference between expected bond energies for the normal covalent bond and experimentally determined values Pauling calculated the values of

• Ionization potential of elements A
• Electron affinity of elements B
• Electronegativity of elements C
• Bond length D

Ionic radius, in a period from left to right

• Increases A
• Decreases B
• Decreases then increases C
• Increases and decreases D

The shape of CIO^-₃according to valence shell electron pair repulsion theory will be

• Planar triangle A
• Pyramidal B
• Tetrahedral C
• Square planar D

Which of the following geometry is associated with the compound in which the central atom assumes sp³d hybridization?

• Planar A
• Pyramidal B
• Angular C
• Trigonal bipyramidal D

The electron affinity of chlorine may be represented by the equation

• 
  A
• 
  B
• 
  C
• 
  D

Molecular orbital picture of N₂ indicates

• One unpaired electron A
• Two unpaired electron B
• No unpaired electron C
• None of these D

Which of the following molecules has a net dipole moments

• CO₂ A
• CS₂ B
• SO₂ C
• CCI₄ D

During the formation of a chemical bond the potential energy of the system

• Decreases A
• Increases B
• Does not change C
• None of these D

The electronegativeities of F,Cl,Br and I are 4.0,3.0,2.8,2.5 respectively.Hydrogen halide with a high percentage of ionic character is

• HF A
• HCL B
• HBr C
• HI D

Shape of CIO₃is

• Triangular pyramidal A
• Tetrahedral B
• Triangular planar C
• Triangular bipyramidal D

• Excitantion of an electron from 2s to 2p-orbital A
• Transfer of three electrons from B to the other atoms B
• Excitation of two electrons form 2s orbital to 2p orbital C
• Formation of molecular ion D

Inter molecular forces in solid hydrogen are

• Covalent forces A
• Van der Waal forces or London dispersion forces B
• Hydrogen bonds C
• All of these D

The bond order in No is 2.5 while that in NO⁺is 3.Which of the following statements is true for these two species?

• Bond length in NO⁺is greater than in NO A
• Bond length in unpredictable B
• Bond length in NO⁺is equal to that in NO C
• Bond length in NO is greater than in NO⁺ D

On the basis of VSEPR theory SO₂is a

• Liner molecule A
• A bent molecule B
• A strong molecule C
• A gaseous molecule D