Chemical Reactions & Types

precipitate

Solid compound produced from 2 liquids during a chemical reaction. Sign of a chemical reaction.

bubbles

Gas given off during a chemical reaction; may or may not have an odour. Sign of a chemical reaction.

signs of a chemical reaction

change in temperature, formation of bubbles, precipitate forms, color change, change in smell, difficult to reverse

subscript

Number written after and BELOW an element in a chemical formula telling you how many of the preceding element are needed for that compound or molecule.

chemical equation

Written representation of a chemical reaction/chemical change; shows all the reactants and products. Always in the form of: Reactants arrow Products.

chemical change

When substances interact with each other. Original substances are used up. Chemical Reaction

physical change

When a substance changes its phase (changes to a solid, liquid , gas, or plasma) or is modified (size, shape, etc) but remains the same substance.

compound

Any amount of a chemical combination of 2 or more different atoms.

molecule

A chemical combination of 2 or more nonmetals held together by covalent bonds

chemical reaction

the process by which one or more substances change to produce one or more different substances

chemical equation

a representation of a chemical reaction that uses symbols to show the relationship between the reactants and the products

reactants

things that react together (on the left side of the equation)

products

things that are produced (on the right side of the equation)

coefficient

numbers written to balance a chemical equation in front of the element or compound

law of conservation of mass

mass is neither created or destroyed, only transformed during reactions, which is why we balance chemical equations

yield

to produce

single replacement reaction

a chemical reaction in which one element takes the place of another element in a compound

double replacement reaction

a chemical reaction between two compounds where the positive ion of one compound is exchanged with the positive ion of another compound

decomposition reaction

a chemical change in which a single compound is broken down into two or more simpler products

synthesis reaction

a chemical reaction in which two or more substances react to yield a single product

combustion reaction

a chemical change in which an organic compound reacts with oxygen to yield CO₂ and H₂O