Writing and Balancing Chemical Equations (Sec 9.2 pg 235-238)

According to the law of conservation of mass the amount of each atom you start with is the same as the amount of each atom you end with. A skeleton equation is a chemical equation that has not yet been balanced. It does not satisfy the law of conservation of mass…yet.

In order to balance a chemical equation we need to count the number of each type of atoms.

The number in front of a compound (called a coefficient)represents how many molecules are present of that compound. 5 CO = five molecules of carbon monoxide.

CH2 = 1 carbon and 2 hydrogen. As you know, any subscript number only applies to the compound in front of it. CH2 = 1 carbon and 2 hydrogen.

Anything in brackets is treated as a group. 2(CO3) = 2 carbon and 6 oxygen (CO3)2 = 2 carbon and 6 oxygen

There are lots of strategies you can use to balance equations. Your textbook outlines one strategy. Let’s take a look at how that strategy works

Element Before After C 6 1 H 12 2 O 8 3 C6H12O6 + 6O2 6CO2 + 6H2O