When you attempt to "burn" water in a microwave, you won't actually burn the water itself. Instead, you can superheat it, leading to a potentially dangerous situation.
Normally, when water is heated in a microwave, it boils and turns into steam, which helps release the excess energy. However, in some cases, water can be heated beyond its boiling point without actually boiling, due to the lack of nucleation sites for bubbles to form. This is known as superheating.
Superheated water can be unstable, and any disturbance or introduction of impurities (such as a spoon or other object) can trigger a sudden and violent boil. This can result in an explosion of hot water and steam, causing burns and other injuries to anyone nearby.
So, while you won't burn water in the traditional sense, you can create a hazardous situation if you heat water in a microwave for an extended period without it boiling, and then disturb it in any way. It's essential to handle hot liquids with care and avoid superheating water by using microwave-safe containers and, if necessary, stirring the water after heating to promote even heating and prevent superheating.