Balanced chemical equation

balanced chemical equation

What is a balanced chemical equation?

Answer:
A balanced chemical equation is a representation of a chemical reaction where the number of atoms for each element is equal on both the reactant and product sides. This balance reflects the law of conservation of mass, which states that matter cannot be created or destroyed in a chemical reaction.

Steps to Balance a Chemical Equation:

  1. Write the Unbalanced Equation:
    Start by writing the chemical formulae of the reactants on the left side and the products on the right side of the equation.

    For example:

    \text{H}_2 + \text{O}_2 \rightarrow \text{H}_2\text{O}
  2. Count the Atoms of Each Element:
    List the number of atoms for each element present in the reactants and products.

    For the example above:

    • Reactants: 2 Hydrogen (H), 2 Oxygen (O)
    • Products: 2 Hydrogen (H), 1 Oxygen (O)
  3. Adjust the Coefficients:
    Adjust the coefficients (the numbers in front of the molecules) to balance the number of atoms for each element on both sides.

    For the example above:

    • To balance the oxygen atoms, we can place a coefficient of 2 in front of \text{H}_2\text{O}:
      \text{H}_2 + \text{O}_2 \rightarrow 2\text{H}_2\text{O}
    • Now, recount the atoms:
      • Reactants: 2 Hydrogen (H), 2 Oxygen (O)
      • Products: 4 Hydrogen (H), 2 Oxygen (O)
    • To balance the hydrogen atoms, place a coefficient of 2 in front of \text{H}_2:
      2\text{H}_2 + \text{O}_2 \rightarrow 2\text{H}_2\text{O}
  4. Verify the Balance:
    Ensure that the number of atoms for each element is the same on both sides of the equation.

    For the balanced equation:

    • Reactants: 4 Hydrogen (H), 2 Oxygen (O)
    • Products: 4 Hydrogen (H), 2 Oxygen (O)
  5. Simplify Coefficients (if necessary):
    Make sure the coefficients are in the simplest whole-number ratio.

Example of a Balanced Chemical Equation:

Consider the combustion of methane (\text{CH}_4):

\text{CH}_4 + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}
  1. Unbalanced Equation:

    \text{CH}_4 + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}
  2. Count the Atoms:

    • Reactants: 1 Carbon (C), 4 Hydrogen (H), 2 Oxygen (O)
    • Products: 1 Carbon (C), 2 Hydrogen (H), 3 Oxygen (O)
  3. Adjust Coefficients:

    • To balance hydrogen, place a coefficient of 2 in front of \text{H}_2\text{O}:
      \text{CH}_4 + \text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O}
    • Recount the atoms:
      • Reactants: 1 Carbon (C), 4 Hydrogen (H), 2 Oxygen (O)
      • Products: 1 Carbon (C), 4 Hydrogen (H), 4 Oxygen (O)
    • To balance oxygen, place a coefficient of 2 in front of \text{O}_2:
      \text{CH}_4 + 2\text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O}
  4. Verify the Balance:

    • Reactants: 1 Carbon (C), 4 Hydrogen (H), 4 Oxygen (O)
    • Products: 1 Carbon (C), 4 Hydrogen (H), 4 Oxygen (O)

The balanced equation is:

\text{CH}_4 + 2\text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O}

By following these steps, you can balance any chemical equation, ensuring that it adheres to the law of conservation of mass. Balancing chemical equations is a fundamental skill in chemistry that allows for the accurate representation of chemical reactions.

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