Introduction to Chemical Reactions

Active learning helps students move beyond memorizing definitions by engaging with the abstract concepts of chemical bonding through hands-on tasks. These activities allow students to test predictions, observe patterns, and correct misunderstandings in real time, which builds deeper conceptual understanding.

• 5th Year
• Foundations of Matter and Chemical Change
• 3 activities
• 15 min–50 min

Learning Objectives

1. Identify observable indicators of a chemical change, such as gas production, color change, or temperature change.
2. Compare and contrast physical changes with chemical changes, providing specific examples of each.
3. Explain the formation of new substances through a simple chemical reaction, using the baking soda and vinegar reaction as a model.
4. Classify observed changes as either physical or chemical based on evidence.

Inquiry Circle

⏱ 25 min·Pairs

Inquiry Circle: Electronegativity Tug-of-War

Students use a table of electronegativity values to play a 'tug-of-war' game. They calculate the difference between two atoms; if the difference is high, it's an ionic 'win' (transfer), and if it's low, they must negotiate a 'shared' covalent bond.

Prepare & details

What happens when we mix baking soda and vinegar?

Facilitation Tip: During the Electronegativity Tug-of-War, assign roles clearly so all students participate in calculating differences and predicting bond types.

Setup: Groups at tables with access to source materials

Materials: Source material collection, Inquiry cycle worksheet, Question generation protocol, Findings presentation template

• Analyze
• Evaluate
• Create
• Self-Management
• Self-Awareness

Stations Rotation

⏱ 50 min·Small Groups

Stations Rotation: Properties Lab

Set up stations with samples of salt, sugar, wax, and copper. Students test solubility, conductivity (solid vs. aqueous), and melting points, then work in groups to work backwards and identify the bonding type based on their observations.

Prepare & details

How can we tell if something new has been made?

Facilitation Tip: Set up the Properties Lab with labeled stations and timed rotations to keep students focused on comparing ionic and covalent compounds.

Setup: Tables/desks arranged in 4-6 distinct stations around room

Materials: Station instruction cards, Different materials per station, Rotation timer

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Think-Pair-Share

⏱ 15 min·Pairs

Think-Pair-Share: The Octet Rule Exceptions

Provide examples like BF3 or SF6 that don't follow the octet rule. Students think about why these might exist, then pair up to discuss how the 'rules' of chemistry are often models that have specific limits.

Prepare & details

Are all changes chemical changes?

Facilitation Tip: In the Think-Pair-Share on octet rule exceptions, circulate and listen for misconceptions like expanded octets in sulfur or phosphorus before guiding the discussion.

Setup: Standard classroom seating; students turn to a neighbor

Materials: Discussion prompt (projected or printed), Optional: recording sheet for pairs

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

Teaching This Topic

Experienced teachers approach this topic by using analogies carefully, avoiding oversimplifications that create misconceptions later. Focus on helping students connect the abstract ideas of electronegativity and electron distribution to observable properties like solubility and melting points. Use formative assessment throughout to address gaps before they become ingrained.

What to Expect

By the end of these activities, students should be able to predict bond type using electronegativity, explain the difference between ionic lattices and covalent molecules, and identify evidence of chemical change. Successful learning is evident when students justify their reasoning with both data and models.

Watch Out for These Misconceptions

Common Misconception

During the Collaborative Investigation: Electronegativity Tug-of-War, watch for students interpreting ionic bonds as simple attractions between two atoms rather than a repeating lattice.

What to Teach Instead

Use the 3D crystal lattice models or stack oranges to show the repeating structure, and ask students to describe how the tug-of-war analogy changes when scaled up to many ions.

Common Misconception

During the Station Rotation: Properties Lab, watch for students assuming all covalent compounds are gases or liquids at room temperature.

What to Teach Instead

Provide solid examples like sugar or wax, and ask students to relate their observations to the strength of intermolecular forces rather than bond type alone.

Assessment Ideas

Exit Ticket

After the Collaborative Investigation: Electronegativity Tug-of-War, provide students with three compounds (e.g., MgO, CO2, NaF) and ask them to classify the bond type and justify their answer using electronegativity values.

Quick Check

During the Station Rotation: Properties Lab, ask students to record one property that distinguishes ionic compounds from covalent compounds on a shared whiteboard.

Discussion Prompt

After the Think-Pair-Share: The Octet Rule Exceptions, ask students to share one exception they discussed and explain why it does not follow the octet rule.

Extensions & Scaffolding

• Challenge advanced students to research coordinate covalent bonds and present an example to the class with an explanation of how they form.
• For students struggling, provide a partially completed electronegativity table to guide their predictions during the Tug-of-War activity.
• Deeper exploration: Have students compare the conductivity of solid and dissolved ionic compounds to connect lattice structure to real-world applications.

Key Vocabulary

Chemical Reaction	A process that involves rearrangement of the structure of molecules or compounds, resulting in the formation of new substances.
Chemical Change	A change where a new substance is formed, often with different properties than the original materials. This is typically irreversible.
Physical Change	A change in the form of a substance, but not its chemical composition. The substance remains the same, for example, melting ice.
Reactants	The starting materials in a chemical reaction that combine or react to form new substances.
Products	The new substances formed as a result of a chemical reaction.