1.4 Balancing Chemical Equations

• What is necessary to show what happens in a chemical reaction?

  Understanding chemical equations is necessary.
• What is one way to show a chemical reaction?

  With a word equation.
• What happens when methane burns in oxygen?

  It turns into carbon dioxide and water.
• What do we call the substances that react together in a chemical equation?

  Reactants.
• What do we call the substances produced in a chemical reaction?

  Products.
• What does the single arrow in a chemical equation indicate?

  It shows that the reactants react completely to form the products.
• What is the symbol for methane in a chemical equation?

  $CH_4$
• What is the symbol for oxygen in a chemical equation?

  $O_2$
• Why do we write $O_2$ instead of $O$ in chemical equations?


  Because oxygen exists as a molecule made up of two atoms.
• What is the first step in balancing a chemical equation?

  Ensure the same total number of each type of atom on both sides of the arrow.
• How many carbon atoms are on the left side of the equation $CH_4 +$$O_2 \rightarrow CO_2 +$$H_2O$?


  One carbon atom.
• How many hydrogen atoms are on the left side of the equation $CH_4 +$$O_2 \rightarrow CO_2 +$$H_2O$?


  Four hydrogen atoms.
• How many oxygen atoms are on the left side of the equation $CH_4 +$$O_2 \rightarrow CO_2 +$$H_2O$?


  Two oxygen atoms.
• How many carbon atoms are on the right side of the equation $CH_4 +$$O_2 \rightarrow CO_2 +$$H_2O$?


  One carbon atom.
• How many hydrogen atoms are on the right side of the equation $CH_4 +$$O_2 \rightarrow CO_2 +$$H_2O$?


  Two hydrogen atoms.
• How many oxygen atoms are on the right side of the equation $CH_4 +$$O_2 \rightarrow CO_2 +$$H_2O$?


  Three oxygen atoms.
• What is the first rule of balancing chemical equations?

  You cannot change any of the small numbers in the formulas.
• Why can't we change the small numbers in a chemical equation?

  Because it would change the actual type of chemicals in the equation.
• How do we increase the number of oxygen atoms on the left side of the equation?

  By putting a 2 in front of $O_2$.
• What happens if we need a fractional number of molecules when balancing equations?

  We must round up to the nearest whole number.
• How do we balance the number of hydrogen atoms on the right side of the equation?

  By increasing the number of water molecules.
• What is the process for balancing a chemical equation?

  1. Count the number of each type of atom on both sides.
  2. Adjust coefficients (big numbers) in front of compounds.
  3. Ensure whole numbers are used.
  4. Double-check to confirm balance.
• In the reaction of sulfuric acid and sodium hydroxide, what is produced?

  Sodium sulfate and water.
• How many hydrogen atoms are on the left side of the equation for sulfuric acid and sodium hydroxide?

  Three hydrogen atoms.
• How many sodium atoms are on the right side of the equation for sulfuric acid and sodium hydroxide?

  Two sodium atoms.
• What is the balance of sulfur in the reaction of sulfuric acid and sodium hydroxide?

  One sulfur atom on each side.
• How do we balance sodium in the reaction of sulfuric acid and sodium hydroxide?

  By putting a 2 in front of sodium hydroxide.
• What is the final balance of atoms in the reaction of sulfuric acid and sodium hydroxide?

  Four hydrogens, one sulfur, six oxygens, and two sodiums on each side.
• What are the key steps to check after balancing a chemical equation?

  • Count each type of atom on both sides.
  • Ensure the same number of each atom is present.
  • Confirm that the equation is balanced.