Acids, Bases, Salts, and Chemical Reactions

• The resource provides a series of worksheet tasks related to chemical reactions, acids, bases, and salts
• Students should be familiar with acids, though probably less so with alkalis or bases
• Safety is an important consideration when working with these chemicals

Worksheet 2-6: Magnesium and Oxygen

• Burning a piece of magnesium ribbon in a jar of oxygen forms a new substance
• Determine if this reaction is chemical
• Represent the reaction as a word equation
• Name the reactants and products
• Find out what oxidation is

Worksheet 2-6: Heating Sugar

• Heating a small amount of sugar in a test tube creates two new substances
• Write the reaction using a word equation
• What type of reaction has occurred?

Worksheet 2-6: Heating Limestone

• Heat calcium carbonate (limestone) in a test tube
• The gas produced is passed through limewater
• Write a word equation for the reaction
• State the test for carbon dioxide
• What is the process of breaking a compound into two or more substance called?

Worksheet 3-6: Iron Nail in Copper Sulphate

• An iron nail is placed into copper sulphate solution in a beaker
• Determine if this is a chemical reaction with reasoning
• Place a piece of copper into iron sulphate solution to determine if there is a reaction
• Explain a displacement reaction

Worksheet 3-6: Candle Flame

• Lighting a candle allows students to observe the flame
• Determine what type of reaction is occurring
• Determine what new substances are formed when a candle burns
• Ascertain whether this is an exothermic or endothermic reaction
• Compare respiration to combustion, providing supporting reasoning

Worksheet 3-6: Burning Candle in Water

• Placing a burning candle in a trough of water, then inverting a gas jar over it demonstrates concepts
• What happens to the candle?
• Why does the water rise up in the jar?
• Study how much water has risen up
• What does this indicate?
• What is the test for oxygen?

Worksheet 4-6: Fuels

• Define fuel and list examples
• What is the chemical name of fuel?
• Discover what two substances are formed when a fuel is burnt
• What is called the burning of fuel?
• Write an equation for burning of fuel
• Is burning an endothermic or exothermic reaction?
• Compare respiration with combustion
• Discover what useful product is formed when fuel burns
• State how to cut down the supply of oxygen to a flame to put out fire

Worksheet 5-6: Balancing Equations

• Balance chemical equations like:
  • CO₂ + H₂O → C₆H₁₂O₆ + O₂
  • SiCl₄ + H₂O → H₄SiO₄ + HCl
  • Al + HCl → AlCl₃ + H₂
  • Na₂CO₃ + HCl → NaCl + H₂O + CO₂
  • C₃H₆O₂ + O₂ → CO₂ + H₂O
  • Fe₂(SO₄)₃ + KOH → K₂SO₄ + Fe(OH)₃
  • Ca₃(PO₄)₂ + SiO₂ → P₄O₁₀ + CaSiO₃
  • KClO₃ → KClO₄ + KCl
  • Al₂(SO₄)₃ + Ca(OH)₂ → Al(OH)₃ + CaSO₄
  • H₂SO₄ + HI → H₂S + I₂ + H₂O

Chapter 7: Acids, Bases, and Salts UNIT FLOW CHART

• The study of Acids, Bases and Salts includes answering:
  • What are acids?
  • What are alkalis?
  • Indicators and acid strength
  • Understanding neutralization
  • Useful neutralization reactions
  • Some common salts and their uses

Introduction to Acids and Alkalis

• Alkalies are just as harmful as acids
• Ensure that students wear safety glasses when working with alkalis
• Students this age should not be working with concentrated acids or alkalis
• The palate suggests that sweet is the opposite of sour
• Chemistry works with acids and alkalis and not with sweet and sour
• Many chemical drain cleaners are strong alkalis
• Soap product should be left for a few weeks to ensure all hydroxide has reacted

Lesson 1: Acids and Alkalis

• Explain how acids and alkalis can be identified and distinguished from each other
• Classify acids, alkalis and salts and give examples of each
• Identify the physical and chemical properties of acids, alkalis and salts
• Observe and write the uses of acid, alkalis and salts in daily life
• Strong acid contain more hydrogen ions in solution than weak acids
• Dilute acid contains more water than concentrated acid
• Explain the difference between a base and an alkali
• Test different acids with litmus paper and find out the pH of different alkalis
• Write five properties of acids and alkalis in notebooks

Lesson 2

• Explain how acids and alkalis can be identified and distinguished from each other
• Define pH and its ranges with reference to indicators