Putting water in a microwave oven while it is turned on can be dangerous and should be avoided. The microwave oven uses microwave radiation to heat food and liquids. When water is heated in a microwave, it can rapidly reach the boiling point without forming bubbles, which normally act as nucleation sites for boiling. This phenomenon is known as "superheating."
If the superheated water is disturbed or if something is introduced into the container after heating (like a spoon, coffee granules, or even just movement), it can cause a sudden release of steam and boiling. This can lead to an explosive eruption of hot water, potentially causing burns or other injuries.
To prevent the risk of superheating, it's essential to follow proper guidelines when heating water in a microwave:
Use Microwave-Safe Containers: Only use containers labeled as microwave-safe, as they are designed to withstand the heat and pressure generated in a microwave.
Stir the Water: Before and after heating, stir the water to help create bubbles and prevent superheating.
Use a Microwave Cover: When heating water in a microwave, cover the container with a microwave-safe lid or microwave-safe microwave cover to reduce splatter and evaporation.
Be Cautious When Removing: When taking the container out of the microwave, use oven mitts or a towel to handle it, as the water may be very hot.
Follow the Manufacturer's Instructions: Always follow the microwave oven's user manual and any specific instructions for heating liquids safely.
It's crucial to exercise caution when using a microwave oven, especially with liquids, to prevent accidents and ensure your safety.