What is an appropriate method to calibrate a thermometer once it is placed in the ice water?

Waiting one minute after placing the thermometer in ice water is the appropriate method for calibration. This time frame allows the thermometer to stabilize and accurately reflect the temperature of the ice water, which should ideally be at 32°F (0°C). A full minute provides enough time for the thermometer’s sensing element to equilibrate with the temperature of the ice water, ensuring a precise reading for calibration purposes.

Recording the temperature too soon, such as after just 30 seconds, may lead to an inaccurate measurement as the thermometer may not have fully adjusted to the temperature of the ice water during that brief period. Removing the thermometer after 2 minutes may not provide any additional benefit for calibration and could introduce the variable of heat transfer to the surrounding air. Waiting until the water boils is irrelevant in this context since the goal is to calibrate at the freezing point, not the boiling point. Therefore, waiting one minute is the method that ensures accuracy and effectiveness in the calibration process.