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Atoms can neither be destroyed nor created during a simple chemical reaction. Therefore, in a chemical reaction

The sum of atoms before reaction = the sum of atoms after reaction

A Balanced Equation has the same number of each type of atom on both sides of the arrow.

Introduction to Balancing Chemical Equations

In this video, we'll start out with examples that show the concepts behind balancing chemical equations.

1. Start with a word equation.

2. Write a chemical equations.

3. Visualize the atoms and molecules and how they change.

To figure out if the equations is balanced, we look at the number and type of atoms on each side of the arrow. If the number and type of atom is not the same on both sides, the equation in unbalanced. We need to change the number of one or more of the compounds in order to get the atoms to balance. We do this by placing coefficients (numbers) in front of each of the compounds. When balancing equations, you cannot ever change the subscripts of a compound.

In this video, we'll see the process or trial and error and the steps that you have to go through to balance chemical equations.

1. Keep track of the number of atoms on both sides of the equation.

2. Add coefficients to one or more of the elements and compounds to make the number of atoms equal.

Balancing chemical equations may require some trial and error. There are some general rules that could be helpful, but they may not work all the time.

- Rule 1: Balancing chemical equations using the one’s and two’s technique
- Rule 2: Balancing chemical equations using the two’s and three’s technique
- Rule 3: Balancing chemical equations using the CHO technique
- Rule 4: Balancing chemical equations using the even technique
- Rule 5: Balancing chemical equations containing polyatomic ions

In this page, we will look at some examples of applying

**Rule 1: Balancing chemical equations using the one’s and two’s technique. **

*Example: *

Balance the equation

K + O

_{2}→ K_{2}O

*Solution: *

**Step 1:** On the left side of the equation there are 2 oxygen atoms and on the right side of the equation there is one oxygen atoms. Multiply K_{2}O by the coefficient of 2 to balance the oxygen atoms.

K + O

_{2}→ 2K_{2}O

**Step 2:** Balance the K by placing the coefficient of 4 in front of K

4K + O

_{2}→ 2K_{2}O

**Step 3:** Check that all the atoms balance and make sure that all coefficients are in the lowest-possible ratio.

The following videos show some examples of using the one’s and two’s method to balance chemical equations.

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