Structure & Bonding (Double) quiz

1. What is needed to complete this diagram to show the ionic bonding in potassium oxide, K₂O ?

1) eight electrons around the potassium (any combination of dots and one crosses) 2) A charge of +2 on the oxide and -1 on the potassium 3) A second potassium ion the same as the first

1) eight electrons around the oxide (six dots and two cross) 2) A charge of +1 on the potassium and -2 on the oxide 3) A second oxide ion the same as the first

1) eight electrons around the oxide (six dots and two cross) 2) A charge of +2 on the potassium and -1 on the oxide 3) A second potassium ion the same as the first

1) eight electrons around the oxide (six dots and two cross) 2) A charge of +1 on the potassium and -2 on the oxide 3) A second potassium ion the same as the first

Question 1 of 12

2. Describe the formation of a covalent bond

The sharing of a single electron between two nuclei

The electrostatic attraction between positive metal ions and a sea of delocalised electrons

The sharing of a pair of electrons between two nuclei

The transfer of electrons from one atom to another

Question 2 of 12

3. If a substance has a simple molecular structure, what physical state might it be at room temperature?

Any state

Solid or liquid

Gas or liquid

Solid

Question 3 of 12

4. Typically, do covalent substances conduct electricity?

Yes

Depends on conditions (e.g. pressure, temperature etc.)

Depends on the substance

Question 4 of 12

5. Give the definition of a covalent bond

Strong electrostatic attraction between a shared pair of electrons and a nucleus

Strong electrostatic attraction between a postive ion and a sea of delocalised positive ions

Strong electrostatic attraction between oppositely charged ions

Strong electrostatic attraction between a shared pair of electrons and two nuclei

Question 5 of 12

6. Why is the boiling point of a larger molecule higher than that of a smaller molecule?

Larger molecules have fewer attractions between them. These take less energy to overcome.

Larger molecules have more attractions between them. These take more energy to overcome.

Larger molecules have fewer attractions between them. These take more energy to overcome.

Larger molecules have more attractions between them. These take less energy to overcome.

Question 6 of 12

7. Explain, in terms of its structure, why graphite can act as a lubricant.

Graphite has weak forces of attraction between layers. These layers can slide over each other

Graphite has a low melting point so becomes liquid when heated by friction

Graphite has strong forces of attraction between layers. These layers can slide over each other

Graphite is a smooth metal so creates a surface with little friction

Question 7 of 12

8. Explain, in terms of structure and bonding, why magnesium oxide has a higher melting point than sodium chloride

NaCl and MgO both have a giant ionic structure with strong electrostatic forces between oppositely charged ions. The Ions in MgO have a charge of 2 and -2, but in NaCl the charges are 1 and -1. So the bonds in MgO require more energy to break

Mg²⁺ and O²⁻ ions are larger than sodium and chloride therefore the electrostatic forces between the ions are much stronger. This requires more energy to break.

Sodium chloride is a simple molecular substance so there are only weak intermolecular forces which require little energy to break

Magnesium and oxygen are more reactive elements

Question 8 of 12

9. Explain the term ionic bond

An ionic bond is the strong magnetic attraction between oppositely charged ions

An ionic bond is the strong electrostatic attraction between oppositely charged ions

An ionic bond is the strong electrostatic attraction between a shared pair of electrons and two nuclei

An ionic bond is the strong electrostatic attraction between similarly charged ions

Question 9 of 12

10. Explain why Silica, SiO₂ is a solid with a high melting point

Silica has a simple molecular structure with weak intermolecular forces that require little energy to overcome

Silica has a giant covalent structure with many strong covalent bonds that need a lot of energy to break

Silica has a giant metallic structure with weak forces of attraction between layers

Silica has a simple molecular structure with strong intermolecular forces that require a lot of energy to overcome

Question 10 of 12

11. When can ionic substances conduct electricity?

Never

When molten or dissolved

In any state

Only when molten

Question 11 of 12

12. In the dot and cross diagram of the outer electrons showing the covalent bonding in a molecule of hydrogen (H₂), how many electrons should be shown in areas 1, 2 and 3?

There should be seven electrons in areas 1 and 3, and two electrons in area 2

There should be seven electrons in areas 1 and 3, and four electrons in area 2

There should be six electrons in areas 1 and 3, and two electrons in area 2

There should be zero electrons in areas 1 and 3, and two electrons in area 2

Question 12 of 12

Structure & Bonding (Double) quiz

Related Posts:

Share This Story, Choose Your Platform!