ECAT Pre Engineering Chemistry Chapter 6 MCQ Test With Answer

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

Which of the following has highest bond order

• 
  A
• 
  B
• 
  C
• 
  D

The equation for the first ionization energy of hydrogen is

• 
  A
• 
  B
• 
  C
• 
  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

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

• H₂O A
• NH₃ B
• HCl C
• CO₂ 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 structure of ICI₂is

• Trigonal A
• Trigonal bipyramidal B
• Octahedral C
• Square planar D

The number of antibonding electron pairs in O^2-molecular ion on the basis of MOT is

• 4 A
• 3 B
• 2 C
• 5 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

Which of the following molecules have multiple bonds

• CH₄ A
• C₂H₄ B
• C₂H₆ C
• CCI₄ D

Mg becomes isoelectronic with neon when it

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

Atoms obey octet rule by sharing-electrons making covalent bonds according to

• Lewis and Kossal theory A
• Valance bond theory B
• VSEPR theory C
• Molecular orbital theory D

Antibonding MO is formed by

• Addition of atomic orbitals A
• Substraction of atomic orbitals B
• Multiplication of atomic orbitals C
• None of these D

The geometry of 4 sp³hybrid orbitals on an atom is

• Square planar A
• Tetrahedral B
• Trigonal planar C
• Linear D

The shape of the molecule SF₂Cl₂is

• Trigonal bipyradmidal A
• Cubic B
• Octahedral C
• Tetrahedral D

The number of bonds in nitrogen molecule is

• 
  A
• 
  B
• 
  C
• 
  D

Which for the following has no dipole moment

• HCI A
• H₂S B
• H₂O C
• CO₂ D

XeF₄has shape of

• Sphere A
• Trigonal bipyramidal B
• Tetrahedral C
• Square planar D

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

• Ca A
• Ba B
• K C
• Al D

All covalent bonds formed between the two atoms are non-polar when

• Covalent bond between two non-metal atoms A
• Covalent bond between metal and non-metal B
• Covalent bond between two atoms of same element C
• Covalent bond between metal atoms 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

• 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

Generally the bond formed by metals with non-metals is

• Ionic A
• Covalent B
• Polar C
• Non- polar D

Generally ionization energy of atoms decreases by

• Decreases in atomic size A
• Increase in atomic size B
• Increase in nuclear charge C
• None of these D

Three sp²hybrid are co-planar at an angle of

• 104.5° A
• 109.5° B
• 107° C
• 120° 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 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

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

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

When of the following is isolelectronic with krypton

• Ca⁺⁺ A
• Al⁺⁺⁺ B
• Br^-1 C
• I^-1 D