ECAT Pre Engineering Chemistry Chapter 6 MCQ Test With Answer

In which of the following theories the hybridizationis considered

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

The boiling point of heavy water is

• 108°C A
• 101.4°C B
• 99°C C
• 110°C D

The bond order O₂molecule is

• 1 A
• 2 B
• 3 C
• Zero D

Which of the following statements is not correct regarding bonding molecular orbitals?

• Bonding molecular orbitals possess less energy than atomic orbitals from which they are formed A
• Bonding molecular orbitals have low electron density between the two nuclei B
• Every electron in the bonding molecular orbitals contributes to the attraction between atoms C
• Bonding molecular orbitals are formed when the electron waves undergo constructive interference D

Mg becomes isoelectronic with neon when it

• Loses two electrons A
• Gains two electrons B
• Loses 1 electron C
• Gains 1 electron D

Ionic radius, in a period from left to right

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

The atomic radius of hydrogen is 37

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

In a group the atomic size increase downward due to

• Addition of electronic shells A
• Increase in the proton number B
• Repulsion of electrons C
• All of the above D

The overlapping of two partially filled atomic orbital is in such a way that the probability of finding the electron pair is maximum along the axis joining the two nuclei, the bond is

• Sigma bond A
• Pi bond B
• Ionic bond C
• Non-polar bond D

The bond angles in methane CH₄are equal to

• 109.5° A
• 107.5° B
• 104.5° C
• 120° D

• The ionization energy of A is high and electron affinity of B is low A
• The ionization energy of A is low and electron affinity of B is high B
• Both the ionization energy of A and electron off affinity of B are high C
• Both the ionization energy of A and electron affinity of B are low D

The electron affinity of chlorine may be represented by the equation

• 
  A
• 
  B
• 
  C
• 
  D

Noble gases have the electronic configuration with their valance shell ns²np⁶except one

• He A
• Ne B
• Kr C
• Xe D

According to MO Theory, the species O₂+ possesses

• bond order of 2.5 A
• three unpaired B
• diamagnetic character C
• stability lower then O₂ D

Molecular orbital picture of N₂ indicates

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

The equation for the first ionization energy of hydrogen is

• 
  A
• 
  B
• 
  C
• 
  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

Water H₂O is liquid while hydrogen sulphide H₂S is a gas beause

• Water has higher molecular weight A
• Hydrogen sulphide is a weak acid B
• Sulphure has high electronegativity than oxyhe C
• Water molecules associate through hydrogen bonding D

Number of sigma bonds in P₄O₁₀is

• 6 A
• 7 B
• 17 C
• 16 D

The shape of gaseous SnCl₂is

• Tetrahedral A
• Linear B
• Angular C
• T-shaped D

Shape of CIO₃is

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

Which of the following molecules has unpaired electrons in anti-bonding molecular orbitals?

• O₂ A
• N₂ B
• Br₂ C
• F₂ D

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

• H₂O A
• NH₃ B
• HCl C
• CO₂ D

The bond order for He₂molecule is

• zero A
• 1/2 B
• 1 C
• 2 D

In sp²hybridization bond angle is _____

• 120° A
• 180° B
• 109.5° C
• None D

Which carbon is more electronegative?

• sp³- hybridized carbon A
• sp-hybridized carbon B
• sp²-hybridized carbon C
• always same irrespective of its hybrid state D

• 154 pm A
• 133 pm B
• 120 pm C
• 150 pm D

Ca, Mg, Be, Ba, belong to the same group, the order of their ionization energy values is

• Be > Mg> Ca > Ba A
• Ba > Ca > Mg > Be B
• Ca > Mg > Be > Ba C
• Ba > Mg > Ca > Be D

Covalent compounds are soluble in

• Polar solvents A
• Non-polar solvents B
• Concentrated acids C
• All solvents D

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

• 1.6 A
• 1.7 B
• 1.8 C
• 1.0 D