### All College Chemistry Resources

## Example Questions

### Example Question #2 : General Topics

When balanced, what is the value of in the following chemical equation?

**Possible Answers:**

**Correct answer:**

Recall that a balanced chemical equation has the same number of each element on one side.

Start by counting the number of each element on each side.

There are the following numbers of moles of each reactant:

There are the following numbers of moles of each product:

Add coefficients in front of the molecular compounds in the equation until there are the same numbers of sulfur, oxygen, lithium, and selenium on each side.

The balanced chemical equation is the following:

Both products and reactants now have the following number of moles:

Since the coefficient in front of is , must equal to .

### Example Question #1 : Balancing Chemical Equations

Balance the following chemical equation:

**Possible Answers:**

**Correct answer:**

A balanced chemical equation will have the same number of each atom on both sides of the reaction.

Start by balancing the number of nitrate.

Since we have nitrate on the left, we must also have nitrate on the right.

This equation now gives potassium on the left, and potassium on the right. Balance the potassium.

This equation is balanced because there are equal numbers of each atom on both sides.