Earlier in this course, you learned that chemists use chemical equations to represent chemical reactions. For example, have you ever consumed a carbonated beverage like soda or sparking water?
These beverages are water-based, with various chemicals added to them. The carbonation, or “bubbly” nature, is caused by adding carbon dioxide to the water.
We can represent this chemical reaction by a chemical equation that shows the chemical formulas for the reactants, water \(\left( \text{H}_{2}\text{O} \right)\) and carbon dioxide \(\left( {\text{C}\text{O}}_{2} \right)\), as well as the product, carbonic acid \((\text{H}_{2}\text{CO}_{3})\).
\(\text{H}_{2}\text{O} + \text{CO}_{2} \rightarrow \text{H}_{2}\text{CO}_{3}\)
Chemical equations like this one allow us to describe chemical reactions clearly and quickly. The reactants are always written on the left side of the arrow, and the products are written on the right side. The arrow is read as “yields,” “produces,” “reacts to produce,” or “forms.” When there are two or more reactants or two or more products, the individual reactants or products are separated from one another by a plus sign.
How well do you remember how to identify the parts of a chemical equation? Find out by completing the next activity. Read the description of the reaction.
Table salt \(\text{(NaCl)}\) is formed through the violent reaction of sodium metal and chlorine gas. The reaction is represented in the following chemical equation.
\(2\text{Na} + \text{Cl}_{2}\ \rightarrow 2\text{NaCl}\)
Let's Practice
Answer each of the following questions using the equation above, then click the question to check your answer.
Identify the reactant(s).
The reactants are \(\text{Na}\) and \(\text{Cl}_{2}\)
The reactants appear on the left side of the arrow in the chemical equation.
Identify the product(s).
The product is \(\text{NaCl}\).
The products appear on the right side of the arrow in the chemical equation.
What part of the chemical equation can be read as “yields” or “react to produce?”
The arrow (\(\rightarrow\))
