A state where the shape and volume don’t change.
What state of matter is solid?
A change in the form of a substance without changing what it is.
What is a physical change?
A change that creates a new substance.
What is a chemical change?
A mixture where one thing is dissolved in another.
What is a solution?
A pure substance made of one type of atom.
What is an element?
The basic unit of matter, made up of protons, neutrons, and electrons.
What is an atom?
How do gas particles move?
Gas particles move freely and quickly in all directions.
An example of a physical change.
Cutting paper or melting ice.
An example of a chemical change.
Burning wood or rusting metal
What does the solvent do in a solution?
The solvent dissolves the other substance.
A substance made of two or more elements combined.
What is a compound?
It shows how many molecules or units of a substance are involved in the reaction.
What is a coefficient?
What happens when you compress a gas?
The gas takes up less space.
How can you undo a physical change?
By reversing the change, like freezing melted water.
How is a chemical change different from a physical change?
A chemical change makes a new substance; a physical change does not.
How can you make a solution stronger?
Add more of the substance being dissolved.
How do elements form compounds?
By chemically bonding together.
It indicates the number of atoms of an element in a molecule.
What is a subscript?
Describe particles in a liquid.
Particles in a liquid are close together but can move around each other.
How does energy affect physical changes?
Energy is used to change the state, like heating to melt ice.
What are 4 signs of a chemical change?
Color change, gas production, precipitate formationm and change in temperature.
How does heat affect solubility?
Heat can help more of the substance dissolve.
How do you separate a compound into elements?
Through chemical reactions, like breaking bonds.
How many atoms in H2O?
3 atoms
How does heat affect states of matter?
Heat can change solids to liquids and liquids to gases.
Why is melting ice a physical change?
Because the water is still H2O, just in a different form.
Why is burning wood a chemical change?
Because it creates ash, gas, and other new substances.
How do you separate a solute from a solvent?
You can evaporate the solvent to leave the solute behind.
How are elements and compounds different?
Elements are single types of atoms; compounds are made of two or more elements.
How do coefficients affect the number of atoms in a chemical reaction?
Coefficients multiply the number of atoms of each element in the formula.