Notes on Chemical Equations

During a chemical change, substance and form new substances

Chemical Equations A Chemical Equation is a sentence that describes what happens during a chemical change

Reactants The original substances are the ones you have at the beginning. They are called reactants because the take part in the chemical reaction. Written on the left side.

 Means yields or produces

Products The new substance formed during a chemical reaction is called the product and is written on the right side of the equation

Energy It takes energy to break the chemical bonds.

Subscripts and Coefficients The subscript is the small number that hangs below the line. It tells how many atoms of each element are found in the molecule. The coefficient is the large number in the front of the formula of the substance. It tells how many molecules of the substance there are.

Identify the subscripts and coefficients.

Law of Conservation of Mass Total amount of mass and energy in the universe always remains the same

Balancing Equations An equation must be balanced. You must have the same number of atoms on both sides of the arrow in the equation.