Ch11 (CC)

• What are chemical changes defined as?

  Rearrangement of atoms that aren't created or destroyed
• What does it mean that mass is conserved during a chemical change?

  It means that the total mass of reactants equals the total mass of products
• What is a physical change?

  It is a change where matter changes form or state but not chemical identity
• What are examples of physical changes?

  Dissolving, evaporation, and boiling
• What characterizes a chemical change?

  It forms new products and is irreversible
• What are the two types of chemical changes?

  Combination of substances and breakdown of substances
• What are reactants in a chemical reaction?

  Substances that chemically combine to form new products
• What are products in a chemical reaction?

  New substances formed from reactants
• What does the notation $2H_2O$ mean in the equation?


  It means there are 2 molecules of water, each containing 2 hydrogen atoms
• What happens if the beaker is open during a chemical reaction?

  The mass of any gas produced, such as oxygen, may not be measured by the electronic balance as it escapes the beaker
• How does combustion differ from thermal decomposition?

  Combustion involves heating a substance in the presence of oxygen to form new substances, while thermal decomposition involves breaking down a substance upon heating
• What is thermal decomposition?

  It is when a substance breaks down upon heating into two or more simpler substances
• What occurs during oxidation?

  A substance gains oxygen
• What is the process of neutralisation?

  A chemical reaction between an acid and an alkali
• What are the products of a neutralisation reaction?

  Salt and water
• What is an example of a neutralisation reaction involving hydrochloric acid?

  Hydrochloric acid + Sodium hydroxide → Sodium chloride + Water
• What is an example of a neutralisation reaction involving sulfuric acid?

  Sulfuric acid + Potassium hydroxide → Potassium sulfate + Water
• Which metals do not react with acids?

  Copper, silver, and gold
• What is produced when an acid reacts with a metal?

  A salt and hydrogen gas
• What is an example of a reaction between magnesium and hydrochloric acid?

  Magnesium + Hydrochloric acid → Magnesium chloride + Hydrogen gas
• How can you test for the presence of hydrogen gas?

  By placing a lighted splint at the mouth of the test tube, which will extinguish with a 'pop' sound
• What happens when an acid reacts with a carbonate compound?

  It produces a salt, carbon dioxide, and water
• What is an example of a reaction between magnesium carbonate and hydrochloric acid?

  Magnesium carbonate + Hydrochloric acid → Magnesium chloride + Carbon dioxide + Water
• How can you test for the presence of carbon dioxide?

  By bubbling the gas through limewater, which forms a white precipitate