Chemical Equations C1

• What is the purpose of chemical equations in a chemical reaction?

  To show what is happening during the reaction
• What is an example of a word equation for a chemical reaction?

  Methane burns in oxygen to produce carbon dioxide and water
• What are the reactants in the example of methane burning?

  Methane and oxygen
• What are the products in the example of methane burning?

  Carbon dioxide and water
• What does the single arrow in a chemical equation represent?

  It shows that the reactants react completely to form the products
• What is a symbol equation?

  It uses chemical symbols to represent the molecules involved in a reaction
• What is the chemical symbol for methane?

  $CH_4$
• What is the chemical symbol for oxygen?

  $O_2$
• 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 do you know if a chemical equation is balanced?

  When the total number of each type of atom is the same on both sides
• If you have one carbon atom on the left side of the equation, how many should you have on the right side?

  One carbon atom
• What is the rule regarding changing numbers when balancing chemical equations?

  You cannot change the small numbers in the chemical formulas
• How do you increase the number of oxygen atoms on the left side of the equation?

  By putting a number in front of the $O_2$
• Why can't you use a fraction when balancing chemical equations?

  Because you need to keep whole numbers
• How do you balance the number of hydrogen atoms in the methane combustion example?

  By increasing the number of water molecules
• What are the steps to balance a chemical equation?

  1. Count the number of each type of atom on both sides.
  2. Adjust the coefficients (big numbers) in front of compounds.
  3. Ensure whole numbers are used.
  4. Double-check to confirm all atoms are balanced.
• In the example of sulfuric acid and sodium hydroxide, how do you balance sodium?

  By putting a 2 in front of sodium hydroxide
• What is the final balanced equation for the reaction of sulfuric acid and sodium hydroxide?

  $H_2SO_4 +$$2NaOH \rightarrow Na_2SO_4 +$$2H_2O$
• What should you do after balancing a chemical equation?

  Double-check to see if it is balanced
• What is the total number of atoms in the balanced equation of sulfuric acid and sodium hydroxide?

  Four hydrogens, one sulfur, six oxygens, and two sodiums on each side
• What are the common challenges when balancing chemical equations?

  • Ensuring the same number of each type of atom on both sides
  • Avoiding changing small numbers in formulas
  • Keeping whole numbers for coefficients
  • Adjusting multiple elements simultaneously