OZ Kerboodle Test (MCQ's)

Question 1

1-iodobutane has a higher boiling point than 1-bromobutane.

What is the reason?

• 1-iodobutane has stronger instantaneous dipole-induced dipole bonds.
• 1-iodobutane has stronger permanent dipole-permanent dipole bonds.
• Iodine is more electronegative than bromine.
• The C—I bond is stronger than the C—Br bond.

Answer 1

• 1-iodobutane has stronger instantaneous dipole-induced dipole bonds.

Question 2

Which is correct about nucleophilic substitution?

• It involves homolytic bond fission.
• An electron deficient molecule attacks a carbon rich centre.
• A small molecule is eliminated.
• The nucleophile donates a lone pair to an electron deficient centre.

Answer 2

• The nucleophile donates a lone pair to an electron deficient centre.

Question 3

The concentration of CO₂ by volume in the atmosphere is 0.04%.

What is this in ppm?

• 40
• 400
• 4000
• 40000

Answer 3

• 400

Question 4

Which one-step reaction forms ozone in the stratosphere?

• O₂ + O –> O₃
• 3O₂ –> 2O₃
• NO₂ + O₂ –> NO + O₃
• 3O –> O₃

Answer 4

• O₂ + O –> O₃

Question 5

Which is a correct statement about the Sun’s radiation?

• UV is the only radiation emitted.
• UV has a shorter wavelength than IR
• IR has a higher frequency than UV
• Visible has a higher frequency than UV

Answer 5

• UV has a shorter wavelength than IR

Question 6

Which is a correct statement about ozone?

• It causes photochemical smog in troposphere
• It causes skin cancer
• It allows all UV to pass through it in the stratosphere
• There is none left in the stratosphere

Answer 6

• It causes photochemical smog in troposphere

Question 7

Which is a step in the radical reaction of methane with bromine?

• Br₂ + CH₄ –> CH₃Br + HBr
• Br + CH₄ –> CH₃Br + H
• CH₃ + Br₂ –> CH₃Br + Br
• H + Br₂ –> HBr + Br

Answer 7

• CH₃ + Br₂ –> CH₃Br + Br

Question 8

Which is a correct statement about UV radiation and its interaction with matter?

• It causes bonds to vibrate.
• It causes electrons to move to higher energy levels.
• It cannot break bonds
• It causes heterolytic fission of bonds.

Answer 8

• It causes electrons to move to higher energy levels.

Question 9

Increasing the pressure increases the rate of a reaction.

What is the reason for this?

• More molecules collide
• Molecules are in a smaller area
• Molecules collide more frequently
• A greater proportion of collisions have an energy greater than E_a

Answer 9

• Molecules collide more frequently

Question 10

What is represented by a ‘curly arrow’ in mechanism?

• Movement of an electron
• Movement of positive charge
• Movement of negative charge
• Movement of a pair of electrons

Answer 10

• Movement of a pair of electrons