Using a liquid thermometer

Equipment you’ll need:

For the thermometer:

• Ethanol/rubbing alcohol
• Water
• Food colouring (red)
• Test tube/clear straw

For the experiment:

• Bowl of ice and water
• Bowl of warm water

Please note that this experiment can easily be conducted using an ordinary liquid thermometer, if you are unable to make one in class.

Method:

• Mark a line on the tube of your as it rests at room temperature
• Place the thermometer in the water and ice bowl and observe the liquid drop below your room temperature mark
• Remove the thermometer from the water and ice bowl and place it in the warm water bowl
• Observe the liquid in the thermometer rise up and beyond the room temperature mark

• If you’re making your own thermometer, place a small amount of liquid in the tube and observe it’s reaction to the change in temperature