When studying chemical reactions, balancing equations is a critical step to ensure that the law of conservation of mass is obeyed. This means that the number of atoms of each element on the reactant side of the equation must be equal to the number of atoms of the same element on the product side. Let’s explore how to balance the chemical equation involving carbon dioxide (CO₂) and water (H₂O).
Step 1: Write the Unbalanced Equation
The unbalanced equation for the combination of CO₂ and H₂O is:
CO2+H2O→?
At first glance, we can see that carbon dioxide (CO₂) and water (H₂O) are the reactants, but we need to determine the products.
Step 2: Identify Possible Products
CO₂ and H₂O can combine to form different types of products depending on the reaction conditions. One common product of such a reaction is glucose (C₆H₁₂O₆), as it is a key reaction in photosynthesis. This is represented by the general formula:
CO2+H2O→C6H12O6
Glucose is a simple sugar and an essential molecule for plants, so in the case of photosynthesis, this is one of the most likely products.
Step 3: Balance the Equation
Now, let’s balance the equation for the production of glucose. We need to make sure that the number of atoms for each element on both sides is equal.
The unbalanced equation is:
CO2+H2O→C6H12O6
- Balance the Carbon Atoms: The product contains 6 carbon atoms (C₆) in glucose, so we need 6 CO₂ molecules to match this:
6CO2+H2O→C6H12O6
2. Balance the Hydrogen Atoms: Glucose has 12 hydrogen atoms, and each water molecule (H₂O) contains 2 hydrogen atoms. To balance the hydrogen atoms, we need 6 water molecules:
6CO2+6H2O→C6H12O6
- Balance the Oxygen Atoms: On the left side of the equation, we have 6 CO₂ molecules, each contributing 2 oxygen atoms (6 × 2 = 12 oxygen atoms from CO₂) and 6 water molecules, each contributing 1 oxygen atom (6 × 1 = 6 oxygen atoms from H₂O). So, in total, the left side has 18 oxygen atoms (12 from CO₂ + 6 from H₂O).
On the right side, glucose (C₆H₁₂O₆) contains 6 oxygen atoms. To balance the oxygen atoms, we need to adjust the number of molecules of water. By multiplying water by 6, the total oxygen atoms balance.
After balancing, the equation is:
6CO2+6H2O→C6H12O6
This equation is now balanced, with the same number of atoms for each element on both sides of the equation.
Balancing chemical reactions is essential for understanding how matter interacts in a reaction. In this case, we successfully balanced the reaction between carbon dioxide (CO₂) and water (H₂O) to form glucose (C₆H₁₂O₆), which is a fundamental part of the process of photosynthesis in plants. Balancing such equations is a foundational skill in chemistry and helps ensure that reactions are accurately represented and conserved.