Lab 6: Types of Reactions

Remind Students:

• Goggles MUST be worn whenever ANY group has chemical at their station.
• Review safety
  • HCl and NaOH are caustic. Use caution.
• Make sure they secure all equipment in bin when moving between the cart and their stations.
• All glassware must be cleaned and dry (in their bin) before leaving lab.

When reviewing the protocol explain:

• Signs of a chemical reaction and how to detect each:
  • Temperature change (put finger on the underside of the well plate).
  • Color change (spontanteous ie not blue + yellow = green)
  • Gas evolution (Bubbles but will not be as obvious today as before)
  • Precipitation (solution will become cloudy).
  • pH changes (Use litmus or pH paper today)
• Writing formulas (remind them to make the table to find the correct formula).
• Balancing equations (change coefficient only, not subscripts).
• Types of Reactions (Main Types).
  • Synthesis
  • Decomposition
  • Combustion – we will not see this today.
  • Single Replacement
  • Double Replacement
• Aqueous reaction types
  • Gas Evolving
  • Acid-Base
  • Precipitation
    • Solubility rules –they should have seen this but may review briefly.
  • Redox
    • Oxidation numbers –they should have seen this but may review briefly.

Net Ionic equations – applicable for acid-base AND precipitation reactions. They may need an example of this.

Remind them that for EACH reaction today, they will be responsible for:

• Observing the reaction (signs of a chemical reaction if they occurred)
• Identifying the main type of reaction.
• Identifying the types of aqueous reaction (may be more than 1).

For several reactions they will also be:

• Predicting products (with the correct formula)
• Balancing the chemical equation.