If you bring a substance close to a magnet or magnetically charged object, you may be able to tell if it is polar or nonpolar. Place the substance on a bench and bring the magnet close. Avoid touching the substance with the magnet., If there is any attraction or repulsion from the magnet, your substance is polar. However, that does not mean that the substance is nonpolar if the magnet does not interact. Some polar molecules are not polarized enough to interact with a weak magnet.For example, if you have a running stream of water, a magnet will cause the stream to bend. This shows a clear interaction.
 Microwaves work by using high frequency electromagnetic radiation to cause polar molecules to spin. The spinning creates friction, which creates heat. To test the polarity of your substance, place it in the microwave.Never put metals, flammables, or explosives into a microwave.
If you put water in the microwave, you will notice that it gets hot. It is polar.
If you try putting baby oil in the microwave, you will notice that the microwave doesn’t seem to heat it very well. It is nonpolar.
 When the microwave comes on, the substance will be subjected the radiation. If it is a polar substance, the radiation will make the molecules spin (though this will not be visible). If the substance is nonpolar, the microwaves will have little effect., Look for signs of deformation or melting. Check to see whether the substance is hot. If the microwave affected the substance, it is polar.
Bring the substance close to a magnet.
Look for any interaction.
Put the substance in question in a microwave.
Turn on the microwave.
Observe the substance.
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