Can you think of how many times you have used your microwave today?  To heat up your coffee, a quick nuke to make your lunch more appetizing, and don’t forget the delicious popcorn you ate for snack time after dinner! 

Almost everyone has a microwave in their kitchen.  They have become so common that most people are surprised to hear someone say that they don’t have one.  The reason why we have microwaves in our homes is plain; they are amazingly efficient at heating and cooking foods or liquids.   

The efficiency of the microwave comes from the microwaves themselves.  A microwave oven works by passing radio waves through the food or liquid.  These are not the same kind of radio waves that broadcast Rock94 (one of Thunder Bay’s local radio stations), but instead use a radio wave frequency of 2500 megahertz (Rock94 broadcasts at 94 megahertz).  Radio waves at this frequency have the ability to be absorbed by water, fats, and sugars.  When they are absorbed they make the individual molecules inside start to vibrate, which disperses energy in the form of heat.  In a traditional electric or gas oven, the heat has to move from the outside of the food into the centre (this is called conduction).  In a microwave oven, the molecules become excited and that causes heat everywhere throughout the food (or liquid).  This means that only the item in the microwave is being heated, not the air surrounding it, thus it is more efficient. 

Superheating is a phenomenon that can happen when heating water in the microwave.  Superheating occurs when the water heats up past its point of boiling without releasing any steam.  This means that as soon as the container is bumped, all of the heat can be released at once, causing an eruption of scalding liquid.  If the water is being heated in a container that has no surface scratches or pits in it, it does not provide anywhere for bubbles (steam) to start forming as the water heats up.  Although this is not a common occurrence, there are some things that you can do to avoid it.  

Don’t heat water in a brand new container that has a very smooth surface.

Place a wooden stir stick into the cup before heating it. 

The stick will help to dissipate the heat. Let the container cool in the microwave for 30 seconds before removing it.