15.1 Science Flashcards
a chemical change resulting from a collision between atoms or molecules
chemical reaction
the original substances that undergo a chemical reaction
reactants
the new substances produced by the reaction
products
four observations that indicate that a chemical change occurred
Change in color
Formation of a gas
Formation of a precipitate
Release or absorption of energy
an expression that uses chemical symbols to represent a chemical reaction
chemical equation
the number before each chemical formula that indicates how many molecules or formula units of that substances are involved in the reaction
coefficient
in each molecular formula that indicate the number of atoms of each element in the molecule or formula unit
subscript
the total mass of the reactants is equal to the total mass of the products
law of conservation of mass
A substance that is consumed in a chemical reaction
reactant
A substance that is formed during a chemical reaction
product
a chemical equation that has the same number of atoms of each element on each side of the arrow
balanced equation
a chemical reaction in which two or more substances combine to form a new substance, sometimes called a synthesis reaction
combination reaction
A+B → AB
combination reaction
a chemical reaction in which a compound breaks down, or decomposes, to form different substances
decomposition reaction
AB → A+B
decomposition reaction
