Experimentally you can try dissolving polar and non-polar solids in the solvent. Since like dissolves like polar solids are soluble in polar solvent and vice versa. Remember, however, that advice sometimes fails.
Theoretically, you compare the electronegativity of the elements. In H2O, O has an electronegativity (EN) of about 3.5 and H is about 2.1. So the O end is - and the H end is + and that makes a polar molecule. To be polar a solvent must have two things.
1. It must have a polar bond (example H and O in H2O) AND
2. It must not be symmetrical in space.
Note that BOTH of these must be true for a solvent to be polar. CCl4, for example has polar bonds (4 of them) since each C-Cl bond is polar . However, CCl4 is symmetrical in space; i.e., it is a tetrahedral molecule so that polarity of each bond is canceled.
Students have trouble visualizing how CCl4 as a tetrahedral molecule makes the polarity cancel but CO2 is an easier molecule to show that. The C=O bond is polar since the EN of C is about 2.5 and that of O is 3.5. That makes the C end + and the O end - (and for CO it is polar) but if we make CO2 it looks like this. O=C=O. See that it is a linear molecule and the polarity of the left O=C cancels the polarity of the right C=O. So although EACH C=O bond is polar, the molecule as a whole is not because each one cancels the other. I hope this helps but if you have any further questions about this please don't hesitate to ask.
How do u tell of a solute is polor or non polar based on what
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Dr Bob i would really like to thank you for your time this has greatly helped my learning in school
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