How to Make a Thermometer
Step 1: Mix 74 ml of water with 74 ml of isopropyl alcohol, also known as rubbing alcohol, in a measuring cup. Pour the mixed solution into a bottle with a wide mouth.
Isopropyl alcohol can be purchased from your local pharmacy.
Step 2: Add a few drops of red food coloring to the solution to display the temperature levels more clearly.
Step 3: Use a clear glass dropper to insert into the hole of the plastic bottle, ensuring it is submerged in the water without touching the bottom of the bottle.
Step 4: Wrap clay around the bottle neck to seal off the mouth of the bottle, being careful not to get any clay inside the dropper.
How to Measure Temperature Levels on the Thermometer
Step 1: Mark the water level at room temperature on the thermometer bottle.
Step 2: Place the bottle in a container with hot water and observe the water level rise in the dropper. Draw a line on the bottle or dropper and label it with the actual temperature of the water at that time.
Step 3: Place the bottle in a different container with cold water and observe the water level decrease in the dropper. Record the actual temperature of the water on the bottle at that time.
The solution in your thermometer can only measure temperatures above 0°C and will freeze if it reaches 0°C.
Above is a guide on how to make a homemade thermometer using a water bottle and isopropyl alcohol. Enjoy making and using this quick thermometer at home!