I am quite confused because I was taught in Grade 10 that a NM and a M is ionic, but this year, in Grade 11, my teacher said that a NM and M bonding together can be covalent. Whenever I look at the bond polarity of Potasssium Iodide, Copper II Chloride and Sodium Nitrate, it tells me that the bond is polar. Are these compounds ionic or covalent? Which method should I use? Thank you!
If the difference of electronegativity of the atoms is less than 1.7, the pair of electrons is shared, but it is more shifted to the more electronegative atom. In the case of ionic bonding electron pair is fully transferred to the more electronegative atom. So NaI is covalent polar compound (1.31) CuCl2 is covalent polar compound (1.08) NaNO3 is ionic compound.