ECAT Pre Engineering Chemistry Chapter 6 MCQ Test With Answer

Number of sigma bonds in P₄O₁₀is

• 6 A
• 7 B
• 17 C
• 16 D

Planar geometry of molecules is due to

• sp³hybridization A
• sp²hybridization B
• sp hybridization C
• P - p overlap D

In which of the following theories the hybridizationis considered

• Vsepr A
• Lewis B
• Molecule orbital C
• Valence bond D

Which of the following molecules have sp³hybridized carbon

• CH₄ A
• C₂H₄ B
• C₂H₂ C
• CO₂ D

The shape of methanol, ammonia and water molecule can be explained by assuming

• Sp³ hybridization A
• Sp²hybridization B
• Sp hybridization C
• All of these 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

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 atomic radius of hydrogen is 37

• Pecometer A
• Manometer B
• Angstrom C
• Micrometer 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

According to VSEPR theory, the shape of the water molecule is

• Octahedral A
• Distorted tetrahedral B
• Planar triangle C
• Linear 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

The bond order for He₂molecule is

• zero A
• 1/2 B
• 1 C
• 2 D

Which of the following charge

• Li A
• Be B
• H C
• He D

The driving force for making a bond is

• To attain noble gas electronic configuration A
• To make soled compounds B
• To make different compounds C
• To make gaseous substances D

Which of the following species is paramagnetic?

• CO₂ A
• NO B
• O^2- C
• CN 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

In H₂O molecule the bond angle is

• 90° A
• 109.5° B
• 107° C
• 104.5° D

Among the alkaline earth metals the element forming predominantly covalent compounds is

• Be A
• Mg B
• Sr C
• calcium D

The covalent bonds are

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

Which one of these is weakest?

• Ionest bond A
• Covalent bond B
• Metallic bond C
• Van der Waal's forces D

The most suitable method of the separation of a mixture of ortho and para-nitrophenol mixed in the ratio of 1: 1 is

• Distrillation A
• Crystallization B
• Vapourisation C
• Colour spectrum 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

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

Which is made by coordinate covalent bond

• H₃O⁺ A
• H₂O B
• CH₄ C
• HCl D

The electronegativity of elements in a period from left to right

• Decreases A
• Increases B
• First decreases then increases C
• First increases then decreases 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

Elements have the tendency to attain 8 electrons in their valence shell. This is known as

• Octer rule A
• Hunds rule B
• Pauli exclusion principle C
• Auf ban principle D

The Electro-negatively difference for ionic bond must be greater than

• 1.6 A
• 1.7 B
• 1.8 C
• 1.0 D

B-atom in BF₃has

• sp³hybridization A
• sp²hybridization B
• sp hybridization C
• no hybridization D

A molecule in which sp²hybrid orbitals are used by the central atom in forming covalent bonds in

• He₂ A
• SO₂ B
• PCl₅ C
• N₂ D