Chemical Changes
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Last updated about 1 year ago
18 questions
Sara was excited to be doing a science lab in class with her group. She read through the lab directions carefully and began mixing the chemicals together . As she poured the first chemical into the beaker , it began to bubble and fizz. She then poured in the next chemical carefully and noticed that it began to change color. Her group wrote down their observations in their science journals.
After they wrote down their observations , they began cleaning up their station. Sara carefully picked up the beaker to pour it into the container the teacher had asked them to use to dispose of the liquid properly. When she picked up the beaker , it burned her hand because it was hot and she dropped the beaker onto the floor. She immediately notified the teacher who quickly responded with the supplies necessary to safely clean up the liquid and the broken glass.
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What were the signs of chemical change that Sara observed? Check all that apply
What were the signs of chemical change that Sara observed? Check all that apply
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Match the statement to whether it represents a chemical change or does not represent a chemical change
Match the statement to whether it represents a chemical change or does not represent a chemical change
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
Wood burning into ashes | arrow_right_alt | No chemical change |
Ice melting into water | arrow_right_alt | Chemical change |
Iron rusting over time | arrow_right_alt | Chemical change |
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Match the scenarios with the correct term to describe the process happening
Match the scenarios with the correct term to describe the process happening
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
A green leaf turning yellow in autumn | arrow_right_alt | Physical change |
The formation of water from hydrogen and oxygen | arrow_right_alt | Chemical change |
Cutting a piece of cake | arrow_right_alt | Chemical reaction |
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Categorize these examples as either a chemical change or physical change
Categorize these examples as either a chemical change or physical change
- Slicing of bread
- Melting of ice
- Baking of bread
- Rusting of a bike
- Physical change
- Chemical change
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Determine if a new substance is formed in these examples
Determine if a new substance is formed in these examples
- Corrosion of metal
- Condensation of water
- Combustion of propane
- Evaporation of water
- New substance formed
- No new substance formed
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What is the typical outcome when a chemical change occurs?
What is the typical outcome when a chemical change occurs?
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In a chemical reaction what is never destroyed?
In a chemical reaction what is never destroyed?
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In a chemical reaction, when two solutions are mixed together and a solid forms, what is this solid called?
In a chemical reaction, when two solutions are mixed together and a solid forms, what is this solid called?
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Which of these is NOT an indicator of a chemical change?
Which of these is NOT an indicator of a chemical change?
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What's the difference between physical and chemical changes?
What's the difference between physical and chemical changes?
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Identify the term used to describe a solid substance emerging from a solution post-chemical reaction
Identify the term used to describe a solid substance emerging from a solution post-chemical reaction
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Which of the following is NOT a sign of a chemical change?
Which of the following is NOT a sign of a chemical change?
Chemical changes are fascinating events that occur right before our eyes in our everyday world. They involve the transformation of one substance into another, and this process is called a chemical reaction. You might not realize it, but chemical changes are happening around us all the time!
For instance, when you light a piece of wood on fire, a chemical change takes place. That's because the heat causes the molecules in the wood to rearrange and form new substances—like ash, smoke, and gases. Another example is when an iron nail rusts. It reacts with the oxygen in the air, leading to a brand new substance known as rust, which we often notice as a reddish-brown substance on old metal objects.
So, how can we tell if a chemical reaction has taken place? One of the most common indicators is a change in color. Like when a sliced apple turns brown after being exposed to air, that's a clear sign of a chemical reaction! Other hints can include the formation of bubbles (release of gas), the formation of a solid from a liquid (called a precipitate), heat or light being produced, or even a change in smell.
Remember, the key to a chemical reaction or chemical change is the formation of a new substance. Through this, it’s easy to see that molecules are constantly remixing to help create the world we see and experience every day.
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What is the process called when one substance transforms into another?
What is the process called when one substance transforms into another?
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Which of the following is a sign that a chemical change has occurred?
Which of the following is a sign that a chemical change has occurred?
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When a piece of wood burns, what new substances are formed?
When a piece of wood burns, what new substances are formed?
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According to the test the key difference in a chemical change versus a physical change is
According to the test the key difference in a chemical change versus a physical change is
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This is an example of a physical change on a molecular level
This is an example of a physical change on a molecular level
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Explain what is happening on a molecular level in the picture.
Explain what is happening on a molecular level in the picture.