Define and give examples of polar molecules and dipole moments.

Title: Chemical Bonding & Structure 

NOTE: Kindly share your UPDATED exam paper to the LIVE EXPERT with an updated Case Study (if any)

The assignment for this unit is in two parts. Part one requires you to write an essay that covers the sections outlined in document provided. Part two requires you to deliver a short presentation which demonstrates your understanding of polarisation and intermolecular forces. You are required to write an essay that covers the sections outlined in the ‘assignment questions’ document provided.

Assessment Criteria:

1. Use the Periodic table to identify elements when given electronic configurations
2. Use dot and cross diagrams to illustrate ionic, covalent and dative bonds.
3. Identify the type of bonding when presented with examples of compounds.
4. Apply electron pair repulsion theory to predict the shapes and bond angles in molecules.
5. Explain the physical properties associated with ionic lattices, discrete molecules, giant molecules and metals.
6. Predict structures when given the physical properties of a compound.
7. Describe what is meant by a homologous series and explain how the properties of such a series may change.
8. Interpret structural formulae.
9. Explain what is meant by a structural isomer.

Chemical Bonding & Structure Assignment Questions:

Section One:
Given the following electron configurations, locate these on the periodic table and state which elements they are:

1. 1s²  2s² 2p⁶ 3s² 3p⁶
2. 1s²   2s² 2p⁶ 3s¹
3. 1s²   2s² 2p⁸ 3s² 3p⁴

Section Two:

1. Draw a dot and cross diagram to illustrate each of the following bonds:

• Calcium chloride – Cacl₂
• Methane – CH₄
• Nitric acid - HNO₃

Section Three:

1. Explain the key physical properties associated with iconic lattices, discrete molecules, giant molecules and metals.
2. Describe why iconic lattices are gently brittle.
3. Examine why diamond and graphite have different physical properties. Explain how you can predict their structures given their physical properties.

Section Four:

1. Predict the bond angle and approximate shape of the amide ion (NH₂²).
2. Describe what you understand by electron pair repulsion theory.

Section Five:

1. Describe what you understand by the concept of a homologous series.
2. Explain how the properties in a homologous series change down the series.
3. Describe the differences between displayed formula, structural formula and skeletal formula.
4. Draw the structural and skeletal for But-2-ene.
5. Explain what is meant by a structural isomer.

QUESTION 2
You are required to carry out a presentation which demonstrates your understanding of polarisation and intermolecular forces. The presentation must include the following:

• Define and give examples of polar molecules and dipole moments.
• Predict types of water intermolecular forces.
• Explain the consequences of the multiple hydrogen bonding in water.

Assessment Criteria

1. Define and give examples of polar molecules and dipole moments.
2. Predict types of water intermolecular forces.
3. Explain the consequences of the multiple hydrogen bonding in water
4. Consider the following two reactions and determine if they are ionic based solely on their locations in the periodic table.