Western Treatment Plant Explorer : Teacher Resources : Resource 11
Resource 11
The toilet trap ¹
The purpose of this activity is to see if you can use the equipment provided to stop smells. (Don't worry, the smelly substance we will use is OK.)
You will need:
- a 250 mL beaker
- a funnel
- Plasticine
- a retort stand
- 2 bosshead clamps
- a dropper
- clear plastic tubing.
Steps
- Roll some Plasticine and mould it around the beaker rim. Add some cheap perfume or a few drops of essential oil to the beaker to provide the smell.
- Place the funnel over the beaker and gently press it into the Plasticine. Connect the tubing to the funnel, then bend it into an S-shape, using the stand and clamps to hold it in place (see picture below).
- Leave the equipment for a few minutes, then gently sniff the end of the tubing. Can you smell anything?
- Use the dropper to add water to the tubing until you fill the base of the 'U' part of the tube. Wait for a couple of minutes. Can you smell anything now?
- Write down what you discovered.
A laboratory S-bend.
¹ Based on an activity from: Keith McTaggart and Paul Saddler 1993, Flushing Dunnies, Melbourne Water and Science Teachers Association of Victoria.