ECAT Pre Engineering Chemistry Chapter 6 MCQ Test With Answer

Ionization energies increase from left to right along the period due to

• Increase in nuclear charge A
• Repulsion of electron increases B
• Repulsion of protons increase C
• Atomic size increase along the period 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

Hydrogen chloride molecule contains

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

In H₂O molecule the bond angle is

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

Mg becomes isoelectronic with neon when it

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

The formation of compounds like PF₅, BCI₃, SF₆indicates that

• These halides are ionic A
• These halides are covalent B
• They are Lewis acids C
• Octet rule not obeyed so the rule is not universal 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 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 Electro-negatively difference for ionic bond must be greater than

• 1.6 A
• 1.7 B
• 1.8 C
• 1.0 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

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

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

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

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

On the basis of VSEPR theory SO₂is a

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

The equation for the first ionization energy of hydrogen is

• 
  A
• 
  B
• 
  C
• 
  D

Outer shells of two elements X and Y have two and six electrons respectively. If they combine, the expected formula of compound will be

• XY A
• X₂Y B
• X₂Y₃ C
• XY₂ 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

Ionic radius, in a period from left to right

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

Which one of these is weakest?

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

Which of the hydrogen halides has the highest percentage of ionic character

• HCl A
• HBr B
• HF C
• HI D

When of the following is isolelectronic with krypton

• Ca⁺⁺ A
• Al⁺⁺⁺ B
• Br^-1 C
• I^-1 D

Planar geometry of molecules is due to

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

Size of an anion is increased as compared to its atom because of the

• Addition of new shell A
• Repulsion of electrons in the valence shell B
• Decrease in nuclear charge C
• Increase in the unclear charge 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

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

Covalent compounds are soluble in

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

The shape of gaseous SnCl₂is

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

Which of the following molecules have multiple bonds

• CH₄ A
• C₂H₄ B
• C₂H₆ C
• CCI₄ D