A ____Chemical Reaction_______________________ is a well defined example of a chemical change. A chemical ___ _____chemical equation___________________ can be used to show the changes that occur in a chemical reaction. In a chemical reaction, the substance on the left side of the arrow are the starting substance. These substances are called ___Reactants________________________. The substances on the right side of the arrow are the substances that result from the reaction. These substances are called ____________Products_______________. The arrow is read as either produces or ______yields_____________________. According to the law of conservation of __________mass_________________, atoms are neither lost nor gained during a chemical reaction. This law is illustrated when a chemical equation is ________Balanced___________. When this is done, there will be the same number of ___________atoms________________ of each kind on both sides of the equation. In a chemical equation, the numbers that are placed in front of the symbols and the formulas are called ______________coefficients_____________. They are necessary to keep the ___________________________ of atoms in balance. There are several rules for balancing an equation. First, write the correct ____________(not so sure)_____________ for each reactant and product. Next, choose the coefficients that make the number of atoms of each _______elements(not so sure)________________ on each side of the equation equal. The correctly written formula should not be changed. If you change the formula of a substance, the equation is no longer ___________correct_____________. Changing a formula will indicate a ________Substance___________________ different than the one intended. To balance the equation Mg + O2 à MgO, first choose coefficients to make the number of atoms of each element on each side of the equation equal. You would need to place a coefficient of _________two___________
