MCAT Topic 3 (Post Test)

1. Which row describes the structure and bonding of SiO₂ and SiCl₄?

• A

• B

• C

• D

2. In which species is there a lone pair of electrons in its structure?

• CH₃

• CH₃ ⁺

• CH₃ ^-

• CH₄

3. Which row is correct?

• A

• B

• C

• D

4. Which statement about ions and ionic bonds is correct?

• Bromine atoms has high electronegativity therefore forming negatively charged bromide ions will be stable ions.

• Ionic bonds form between elements in Group VII of the Periodic Table and any metal elements.

• Positive ions are formed when atoms shows the nuclear charge that protons lost.

• Potassium iodide contains negatively charged potassium ions as Group VII which has one valence electron in outer shell.

5. Which statement best explained about graphite using as an electrode?

• It contains ions that can transport freely throughout the structure

• It has a giant covalent structure which has 3 carbons bound together

• It is one kind of metal that can conduct electricity

• It has mobile electrons that can carry charge between hexagonal layers.

6. Which statement present the correct increasing number of lone-pair electron at center atom?

• A

• B

• C

• D

7. Which of the following molecule has smallest bond angle?

• water

• Sulfur dioxide

• Carbon dioxide

• Ammonia

8. Which of the following interaction between these molecules are weakest in nature?

• Hydrochloric acid (HCl)

• Methane (CH₄)

• Sodium chloride (NaCl)

• Sulfur dioxide (SO₂)

9. Which of the following types of intermolecular forces provides the most accurate explanation for why Methanol (CH₃OH) can dissolve in water?

• Hydrogen bonding

• Ion-dipole interactions

• London dispersion forces

• Dipole-Dipole interactions

10. Which statement is correct with best explanation?

• C-H bond in C₂H₂ has the longer bond length than HCN as the double bond in C₂H₂ will longer than triple bonds in HCN.

• Carbonate ion (CO₃^2-) has three resonance hybrids because electron can re-locate between three bonds in structure.

• Due to lots of electron left over in structure of PO₄^3- , they indicate the hydrogen bonding supply other molecules bound.

• BF₃ and NH₃ has the same shape because there are three single bonds presented in both molecules.