Chemical Changes
What is a chemical change?
A chemical change is a change where a new substance is formed with different properties.
what is a physical change?
A physical change is a change in the form or appearance of a substance, but the substance itself stays the same.
What is an experiment?
An experiment is a test done to learn something or discover how things work.
What are properties of substances?
Properties are characteristics used to describe a substance, like color, smell, texture, or density.
What is matter?
Matter is anything that has mass and takes up space.
What is an example of a chemical change?
An example of a chemical change is burning wood or rusting iron.
Give an example of a physical change.
An example of a physical change is ice melting into water.
Why is it important to evaluate results?
It's important to evaluate results to make sure your observations are accurate and your conclusions are correct.
How can properties help you identify a substance?
Properties help identify substances because each substance has a unique set of properties.
What are the states of matter?
The states of matter are solid, liquid, gas, and plasma.
Describe what happens to properties in a chemical change.
In a chemical change, the properties of the original substances change completely, resulting in a new substance with new properties.
How do physical changes differ from chemical changes?
Physical changes do not create new substances, while chemical changes do.
What should you observe in an experiment with mixed substances?
You should observe whether there are signs of physical or chemical changes like bubbling, color change, or temperature change.
List three properties you might measure in an experiment.
Three properties you might measure in an experiment are mass, temperature, and state of matter.
What is a physical change?
A physical change is a change that affects one or more physical properties of a substance without changing its chemical composition.
How can you tell if a chemical change has occurred?
Signs of a chemical change include color change, temperature change, gas production, light, or a new solid (precipitate) forming.
What happens to properties in a physical change?
In a physical change, only physical properties like shape, size, or state of matter change, not the substance itself.
Explain how to design an experiment to test for property changes.
To design an experiment to test for property changes, control your variables, mix substances, and observe and record changes in color, temperature, or state.
What do we mean by "change of properties"?
"Change of properties" means that the way a substance looks, feels, or behaves has been altered.
What is a chemical change?
A chemical change occurs when a substance transforms into a different substance with different properties.
Explain why cooking food is a chemical change.
Cooking food is a chemical change because it creates new substances with different tastes, textures, and smells, and it cannot be reversed.
Describe a real-life situation where a physical change occurs.
A real-life example is tearing a piece of paper — it changes shape but is still paper.
What might you conclude if two substances mix and no change occurs?
If no change occurs, you might conclude that a physical change happened or that the substances did not react chemically.
Why is it important to understand properties when mixing substances?
Understanding properties is important when mixing substances so you can predict reactions and identify changes.
Explain what happens to matter in a phase change.
During a phase change, matter changes from one state to another, but the total amount of matter remains the same.