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Can water be superheated in microwave?

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Can boiling water in microwave explode? Can water that is boiled in the microwave suddenly explode without any warning?

Superheated water is a dangerous phenomenon and a potential microwave danger that should be avoided. This article will discuss the cause of superheated water in the microwave, dangers of superheated liquids in the microwave, can you boil water in the microwave and how to prevent superheating water in the microwave.

Manufactures’ instructions should be carefully followed and carefully consider all recommendations. Superheated water is extremely dangerous and nothing to play around with.

What is superheating water in the microwave?

Closed microwave oven standing on kitchen shelving for efficient reheating and cooking

Superheating is a physical reaction that is sometimes referred to as boiling retardation or boiling delay. The phenomenon occurs when water is heated to a temperature above the boiling point without actually boiling.

How does water exceed the boiling point and not boil? Microwaves heat water unevenly, and the water temperature gets poorly distributed throughout the liquid.

Boiling hot water and steam vapor can get trapped underneath a layer of cooler water temperatures. The surface tension strengthens the water pressure and acts as a barrier that traps in hot water and steam vapor allowing it to become superheated. Water can heat above the boiling point when held under pressure and pockets of steam vapor can develop.

Why does microwave water explode?

Microwaves use electromagnetic radiation to heat water molecules extremely rapidly. As a result, water heats unevenly and some pockets of water heat up faster than others.

Microwave water can explode when it is superheated, or vaporized below areas with cooler temperatures. Large bubbles of water vapor quickly form underneath the surface tension and when the cup or container is shaken the water can erupt in a violent explosion.

Watch this video to see how dangerous it is to superheat water in a microwave!

How to prevent superheating in the microwave

Some people make suggestions that you should never microwave water. Of course there is a risk that it may be superheated, however there are precautions that you can take to safely boil water in the microwave.

Microwaving distilled water is far riskier since it contains less contamination to disrupt the water tension. City tap water has lots of contaminants while distilled water contains far fewer impurities. Superheated explosions can also occur in the microwave when using tap water if the dissolved minerals are not large enough to act as nucleation sites for the bubbles to react with.

Superheated water in a microwave may explode when the container is jostled or even when something is put into it like a spoon, tea bag or instant coffee. The water may boil vigorously or even explode out of the container resulting in very serious burns.

Boiling water in the microwave is quick, simple and safe. Here are 6 easy steps to follow to prevent superheated water explosion in the microwave:

  1. Use a microwave-safe container. Glass or ceramic bowls work the best, but make sure to choose one labeled as “safe for microwave use.”
  2. Do not cover the container. The container must be unsealed while the microwave isrunning.
  3. Place a non-metallic object inside the container. A wooden chopstick, dowel, popsicle stick or skewer sticking out of the water will break the surface tension and prevent superheating water in the microwave.
  4. Heat in 1-minute intervals. Stir in between every 1–minute duration until the water has started to boil.
  5. Tap the side of the container to check for superheating. Use a spoon or stick to carefully tap the side of the cup, bowl or container to disturb the surface tension of the water molecules. Trapped heat is released when the tension is broken. This may cause an explosion so use caution and stand at a distance.
  6. Cautiously remove the container. Use hot mitts to prevent burns from the outside of the heated container or a splash of boiling water.

Boiling water in the microwave is easy to do, however there are certain precautions should be taken to prevent superheating of liquids in the microwave. Use a microwave safe container, heat uncovered, insert a non-metallic object, use 1-minute intervals, and carefully tap the outside of the container before grabbing with your hands.

Things to know before microwaving water or other liquids

With the vast amount of people reheating and boiling water in the microwave around the world, there is a large probability that microwave superheated water happens on a daily basis.

Whether you microwave water for coffee or microwaving a cup of soup, any amount of microwave liquids can be dangerous. Superheated water is a potential microwave danger that you should be aware of when using the kitchen appliance.

Follow manufacturer instructions, and recommended precautions to prevent superheating water in the microwave. Use a microwave safe container, insert a non-metallic object to break the surface tension, heat in 1-minute intervals and stir in between each duration.

Can water be superheated in the microwave