Properties
What are characteristics used to describe a substance?
What are properties
What do scientists use to study things too small to see?
What are models
What are substances made of?
What are atoms
What are the starting substances in a reaction called?
What are reactants
Can atoms be created or destroyed?
What is No
Name one physical property of matter.
What is color, mass, volume, density, or state
Give an example of a scientific model.
What is a diagram, drawing, or physical model
What is a group of atoms bonded together called?
What is a molecule
What are the new substances formed called?
What are products?
During a chemical reaction, what happens to the total mass of the reactants compared to the products?
What is it stays the same
Why do different substances have different properties?
Because they are made of different kinds of matter.
Why are models useful in science?
They help explain or visualize things we can’t directly observe.
Why do substances differ from each other? (think about atoms)
Because of different types and numbers of atoms.
What happens to atoms during a chemical reaction?
They rearrange.
If you start with 10 atoms, how many must you end with?
What is 10 atoms?
Is melting ice a chemical or physical change?
What is a physical change
True or False: Models are exact copies of real objects.
What is False
What does it mean that groups of atoms repeat?
The same pattern of atoms forms a substance.
Do atoms change into different types during reactions?
What is No
Why does mass stay the same in a reaction?
Because atoms are only rearranged, not lost or gained.
Why is density useful for identifying substances?
Because it is a unique property that doesn’t change.
What is one limitation of models?
They may leave out details or simplify reality.
How does changing the number of atoms affect a substance?
It creates a different substance with different properties.
What must happen to ALL atoms in a reaction?
They rearrange to form products.
What happens if atoms seem “missing” after a reaction?
They are still there—just rearranged or in another form.