Chapter 2 Flashcards
What are the four signs of a chemical change?
1) Production of a gas
2) Color Change
3) Transfer of energy (heat)
4) Formation of a precipitate
What is a chemical change?
A change that produces matter with a different composition than the original matter
What is a physical change?
A change which causes the properties of a material to change but not the composition. A new substance is not formed.
What are the two types of physical change?
Reversible and irreversible
What is a physical property?
A quality or condition of a substance that can be observed or measure without changing the substance’s composition.
What are the two types of physical properties?
Intensive and Extensive
What is the difference between extensive and intensive physical properties?
Intensive: the amount of substance does not matter (ex. Color)
Extensive: the amount of substance does matter (ex. Length)
What is a chemical property?
A quality or condition of a substance that can be observed or measured without changing the substance’s composition
What is a reactant?
A substance present at the start of the reaction
What is a product?
A substance produced in a reaction
What is the Law of the Conservation of Mass?
In any physical change or chemical reaction, mass is conserved
What is an exothermic reaction?
A chemical reaction that releases energy in the form of light or heat
What is an endothermic reaction?
A chemical reaction that absorbs energy
