Lab 6: Types of Reactions
- 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).
- Combustion – we will not see this today.
- Single Replacement
- Double Replacement
- Aqueous reaction types
- Gas Evolving
- Solubility rules –they should have seen this but may review briefly.
- 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.