Key Idea.
Section 1
Evidence of Change
How do we know a chemical reaction occurred? We look for new properties. Signs include a distinct color change, the production of a gas (bubbles), or the formation of a solid precipitate from liquids.
These observable signs provide evidence that new substances are being formed, distinguishing a chemical reaction from a simple physical change like melting or mixing.
Section 2
Reactants to Products
A chemical reaction is a transformation process. The starting substances are called reactants, and the ending substances are called products.
Unlike a physical mixture where ingredients can be separated easily, a chemical reaction creates new materials that cannot be turned back into reactants by simple physical means.
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Section 1
Evidence of Change
How do we know a chemical reaction occurred? We look for new properties. Signs include a distinct color change, the production of a gas (bubbles), or the formation of a solid precipitate from liquids.
These observable signs provide evidence that new substances are being formed, distinguishing a chemical reaction from a simple physical change like melting or mixing.
Section 2
Reactants to Products
A chemical reaction is a transformation process. The starting substances are called reactants, and the ending substances are called products.
Unlike a physical mixture where ingredients can be separated easily, a chemical reaction creates new materials that cannot be turned back into reactants by simple physical means.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter