Review ( 1st term)

Which of these species has a trigonal planar structure?

• PH₃

• BCl₃

• H₃O⁺

• CH₃^-

Use your understanding of intermolecular forces to predict which of these compounds has the

highest boiling point.

• HF

• HCl

• HBr

• HI

Which type of bond is formed between N and B when a molecule of NH3 reacts with a molecule of

BF₃?

• Ionic

• Covalent.

• Co-ordinate

• Van der Waals

Which of these atoms has the highest electronegativity?

• Na

• Mg

• Cl

• Ar

Which of these substances does not show hydrogen bonding?

• HF

• NH₃

• CH₃COOH

• CHF₃

Which of these substances has permanent dipole-dipole attractions between molecules?

• CCl₄

• C₂F₄

• (CH₃)₂CO

• CO₂

Which one of the following molecules is not planar?

• BF₃

• NCl₃

• C₂H₄

• HCHO

Predict which one of the following has the highest boiling temperature?

• CH₃COOCH₂CH₃

• CH₃CH₂CH₂CH₂OH

• CH₃CH₂CH₂CH₂CH₃

• CH₃CH₂CH₂CHO

How many electrons are found in a magnesium ion, Mg²⁺?

• 10

• 12

• 14

• 24

Europium has two isotopes. One is ¹⁵³Eu with an abundance of 52.23%.

Which is the other isotope?

• ¹⁴⁹Eu

• ¹⁵⁰Eu

• ¹⁵¹Eu

• ¹⁵²Eu