Aim
To investigate temperature change when acid reacts with alkali.
Method students should know
- Measure a fixed volume of acid into a polystyrene cup.
- Record the starting temperature.
- Add a measured volume of alkali.
- Place a lid on the cup and stir gently.
- Record the highest or lowest temperature reached.
Variables
- Independent variable
- Volume or concentration of alkali.
- Dependent variable
- Temperature change.
- Control variables
- Volume of acid, Starting temperature, Insulation, Stirring method
Safety and common mistakes
- Wear eye protection.
- Clean spills immediately.
- Use dilute acid and alkali only.
- Using a glass beaker and losing heat quickly.
- Recording only the final temperature.
- Not identifying the maximum temperature.