Loading the lesson
Loading the lesson
Search AllRounder.ai
Search the courses, subjects, tracks, games and features, or jump straight to a page.
Search the courses, subjects, tracks, games and features, or jump straight to a page.
Learn it your way
A short class with Sarah and her students. The other ways are under More.
Sign up free to listen. Transcripts are free to read.
Today, we’ll explore physical and chemical changes with two interesting activities. Who can remind us what a physical change is?
A physical change is when the substance does not change its identity, like melting or freezing.
Yeah! Like the melting of ice to water and then back to ice!
Exactly! Now, can anyone explain what a chemical change is?
A chemical change forms a new substance, like when iron rusts or paper burns.
Or when food cooks!
Great examples! Remember, physical changes are usually reversible and don’t form new substances, while chemical changes are often irreversible. Let's do an activity on burning a candle. What changes do you think we might observe?
The wax will melt, which is physical, and it will create smoke, which is chemical!
Well said! Now, let’s perform the activity.
After our candle activity, what physical changes did we observe?
The wax melted into liquid form!
And it turned back to solid when cooled!
Exactly! And what about the chemical changes?
The wax burned and created smoke and gases!
I think the gases are new substances formed from the wax.
Correct! The combustion of wax leads to the formation of new chemicals like carbon dioxide. Great job, everyone!
Now let's explore another activity! We’ll mix vinegar and baking soda. What do you think will happen?
I think we'll see some fizzing!
That’s because a gas forms, right?
Exactly! When we mix them, a chemical reaction occurs. Watch closely!
Look at all that bubbling! That must be carbon dioxide!
Great observation! And what does that tell us about the change?
That it’s a chemical change since new gas forms!
Absolutely! Let’s summarize what we’ve learned from these activities.
Burning wax and melting down, chemical and physical changes abound.
Once there was a candle, it melted and danced, but when it burned, it changed; now the world’s enhanced.
PCC vs. CCC: Physical Change = Can Come, Chemical Change = Cannot Come back.
PCE for Physical Change Events - Temporary and Reversible.
Term
What demonstrates a physical change?
Click to flip
Term
What is an example of a chemical change?
Click to flip
A change in substance where no new substance is formed and the change is often reversible.
A change that results in the formation of one or more new substances with different properties.
A chemical reaction involving the burning of a substance in oxygen.
Substances that undergo a chemical change in a reaction.
New substances formed as a result of a chemical reaction.
The section presents activities that demonstrate both physical and chemical changes, emphasizing the importance of understanding these changes.
This section explores practical activities related to physical and chemical changes, such as burning a candle and mixing vinegar with baking soda. These activities illustrate the key differences between physical and chemical changes, helping students understand how substances transform under various conditions.
In this section, we delve into two specific activities that exemplify both physical and chemical changes. Understanding these concepts is key in chemistry as they help us differentiate between how substances behave in various situations.
These activities reinforce the chapter's concepts about how to identify physical and chemical changes in everyday life.