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Superheated water in microwave

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Have you ever experiences superheated water in microwave? When you try to boil water in microwave, superheated water is something you want to avoid. 

What is superheat water in a microwave? It is water in a state of liquid subjected to a pressure at which its temperatures vary from the usual temperature. The normal boiling point of water is 100℃ = 212℉, and superheat water can reach the extreme temperature of 374℃ = 705℉.

This stable condition of superheated water is a result of high pressure, which tends to increase the point water boils. By this, the water liquid state is able to obtain a state of balance with the pressure at which the vapor is saturated.

When using the microwave to heat water, a greater pressure allows water to reach a relatively higher boiling point than normal meaning the water can be superheated in microwave easily. Without boiling at normal atmospheric pressure, superheated water can be achieved since there is no place for nucleation to occur.

This article explains how superheated water happens in a microwave, and the best ways to avoid it. Answered below are frequently asked questions about superheating water in the microwave and steps you can take to prevent the dangerous state from happening.

What does superheat mean?

The word superheating means a process by which a liquid has been heated relatively higher than its boiling point without the vaporization of liquid occurring. In this case, water happens to boil if bubbles of vapor get bigger and break out on the surface. 

For this to happen, the temperature ought to be relatively higher for the pressure of vapor to be greater than that of atmospheric pressure.

Most unusual water traits are a result of a powerful bond between the hydrogen atoms. A superheat process provides a wide range of temperatures that split hydrogen bonds, hence altering the properties of the water by affecting the pressure.. 

Can water be superheated in a microwave?

Yes, water can be superheated in the microwave. However, the practice should be discouraged since it’s incredibly dangerous. 

If a person heats water in a cup in a microwave, one may observe that there are no bubbles coming out of the cup. The bubbles may be trapped beneath the surface due to pressure, but the superheat water can explode when the cup is jostled. 

This fact of physics is no longer a myth. 

Microwaves operate precisely by warming up water molecules thorough vigorous agitation using energy that transfers friction into heat. This makes water heat up very fast compared to the rate it changes to vapor, thus causing it to be superheated.

Potential Microwave Dangers

There are some dangers that come along with the use of microwaves to superheat water. The following are hazards that can result in injuries while using a microwave to superheat water.

  • Production of sparks can lead to a fire: When some electrical conductors are used, for example, gold, curtly, and aluminum, in a microwave, they generate a lot of electrical charge which may ignite sparks that result in fire.
  • Unbalanced heating: This result because the heating process takes place so much faster that there is a non-uniform electromagnetic field in the oven. This situation causes an unusual case, whereby the contents inside are warmer than the container containing it. This makes a person underestimate the warmth since he/she is going to base judgment on the external temperature of the vessel. Thus, mishandling may cause serious burns.
  • Leakages on the microwave: There exist a screen made of metal on the door of the microwave. When the switch is on, electromagnetic radiation is directed into the microwave, which automatically turns off when the door is open. The screen has some holes which allow a person to look into the microwave, and these holes are relatively smaller than the wavelength of the radiations. If it happens the holes start leaking the radiations to the outside, then it could be very dangerous for the user causing damages to the tissues and cell formations of the person.

Water can be easily superheated in the microwave. And without caution, water may explode and also burn body parts in the blink of an eye. Microwaves are known for uneven heating and must be frequently stirred to distribute temperature throughout a dish. 

To avoid superheated water, stir often to evenly distribute the heat, and also start low power level to give enough interval time to slowly heat to the desired temperature.

What happens when water is superheated?

At a normal circumstance, water boils at 100℃ at room temperature and sea level pressure. This process is evident through the production of bubbles.

During the superheat process, water doesn’t produce vapor bubbles at this temperature (100℃) since the temperature needs to be greater for the pressure producing the vapor bubble to outmatch the air pressure. As a result, water exceeds its boiling point without boiling taking place.

Therefore, the surface tension of the water becomes extremely strong and hinders any occurrence of bubbles on the surface.

The existence of powerful hydrogen bonds in water is broken up through the process, thus changing all physical and chemical properties of water since the structural lattice of water is altered from the pressure change. 

Furthermore, the polarity of water becomes less, which makes it more of a solvent organic in nature. Its solubility increases rapidly, which makes it act like a solvent for both organic material and gases. 

This property makes it a very useful raw material in reacting and used as a catalyst in both industrial and analysis expertise, which helps in extraction and chemical reactions.

Boiling water in microwave explosion

The explosion is an instant outburst of a matter which is accompanied by violent shattering as a result of vigorous changes in mechanical and chemical energy.

Boiling water can explode in a microwave under the following conditions.

  • If jostle water in the cup while removing it from the microwave because the movement makes bubbles form quickly, thus making the water boil up to the surface. The rapid boiling leads to an explosion since all the vapor is released at once. 
  • The cup used in the microwave contains scratches that lead to a surface that is not uniform for the vapor bubbles to form.

When dealing with boiling water in a microwave, there is possibility to explode if not handled properly. When taking a cup of boiling water from the microwave, any movement may cause explosion. 

Carefully observe the cup you are microwaving make sure that there is no scratches or damage to the cup. The indentations can trap air bubble that could eventually trigger an explosion as well.

Tips to avoid superheated water in a microwave

Great news is that no need to worry about explosion of superheated water when boiling water in the microwave when things are done correctly. Other then condition of microwave-safe cup and handling the hot cup safely, here are more tips to help you to avoid superheated water when using microwave:

  • Always insert a non-metallic material into the water before boiling, i.e. a wooden stirrer, ice cream stick or skewer. The rough surface will break the surface tension and normalize the pressure.
  • Do not use a cup that has a scratchy surface.
  • Heat water within the stipulated time suggested by the manufacturer, about 2-3 minutes.
  • Hit the container from the outside a number of times with a long object. If the water is superheated, the jostled movement will force it to erupt inside the microwave and not all over you.
  • Avoid facing the door of the oven directly when it is open. Again, when the door of the appliance opens there is a risk that the movement causes the superheated water to immediately explode.
Superheated water in microwave

Superheating Water in Microwave: Conclusion

Boiling a cup of water in the microwave, as it can be seen from this article, is extremely dangerous because its temperature is much higher than its usual boiling point. Therefore, all precautions listed should be adhered to for the purpose of avoiding injuries.

Superheated water is a state of liquid where the pressure varies from the usual boiling point temperature of water which is 100 degree C or 212 degree F. It is the result of high pressure that is capable of increasing the boiling point. 

Basically, water is heated higher than its boiling point without accompanied by the vaporization of water molecules. Therefore, it is heated to extreme temperatures that can cause an explosion when the surface tension is broken and the pressure normalizes.

Microwaving water is the easiest way to boil, however it can be difficult to avoid a superheated status. It is extremely hazardous and can be a severe hazard if removing the cup incorrectly.

When water is superheated or above the boiling point, it stops producing air bubbles since the temperature is higher than the pressure. It leads to lessen polarity of water which creates nonexistence of bubble on the surface.

This status is very dangerous. When someone goes to take the water out of microwave and bumps the side of the cup, it can bubble quickly causing an explosion. 

However, superheated water in a microwave is avoidable by reducing the risks associated with the condition. Add a non-metallic stick in the water when microwaving to break the surface tension.

Also, avoid old or scratched cups to boil water in a microwave. The abrasions can trap bubbles and prevent boiling from happening. 

Always follow the manufacturer’s guide to heat water with suggested time and temperature setting. 

Simply heating water in the microwave is easy and convenient, but risking any uncertainty if the water is superheated can be tricky. Understand the basic principles for how superheated water is formed and the proper ways to prevent the state of water by following these simple microwave tips.