Thermometer Use and Operation

1. A thermometer is used to measure the temperature of a substance. There are two scales on the thermometer. The Celsius scale is displayed on one side of the thermometer, and the other side displays the Fahrenheit scale. Both scales are important because the Celsius scale is used in science and the Fahrenheit scale is used in other situations.

2. To measure the temperature of a substance, place the thermometer so that the bulb is covered by the substance.

3. To measure the temperature of water, place the thermometer in the water. The bulb of the thermometer should be completely under the water.

4. To measure the temperature of the air, place the thermometer in an open area. The air should be able to surround the bulb.

5. After placing the thermometer in the correct location, observe the glass tube at the center of the thermometer. The glass tube contains alcohol which has been colored red. The level of the alcohol rises when measuring a warm substance. The alcohol level falls when measuring a cold substance.

6. To find the temperature of the substance, watch the alcohol until it stops moving. Find the top of the red alcohol. Locate the line or numbers beside it. Each small line represents 2°. If the level of alcohol lines up with 20 on the Celsius scale, the temperature is 20°C. If the level lines up with the second small line above 20, the temperature is 24°C.