I need to write about $\ceCuCl2$, and also found in Wikipedia the if you subtract electronegativity you get what bond the is:
$$\chi (\ceCl) = 3.16, \quad \chi (\ceCu) = 1.90$$
$$\chi = 3.16 - 1.90 = 1.26$$
$\chi 1.7 \Rightarrow$ ionic
So it need to be yes, really a covalent bond. I beg your pardon one is correct?
You should be mindful with basic associations such as "metal + non-metal = ionic bond". These tend to throw out the idea of knowledge the gaianation.net connected in favour that rote memorization. Keep in mind for example that mixing caesium metal with gold will develop a salt rather of one alloy, caesium auride ($\ceCs^+ Au^-$). Mixing barium metal and platinum can also produce salts, though your structures space somewhat an ext complex. One can likewise argue the there is far-reaching ionic personality in hard xenon difluoride, also though both atoms room non-metals.
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The idea of using electronegativity to identify covalent/ionic character is likewise meant together a beneficial guide, no as a strict rule with black-and-white limits. Firstly, all bonds have both ionic and covalent character; both principles are an oversimplification, and also in reality it is much more correct come say the a bond has actually a certain contribution from each kind of bonding. This method there is a smooth shift from compounds with mainly ionic character and those with mainly covalent character. Also, the inequalities you point out rely on Pauling electronegativities. Electronegativity is how amazing still a hotly questioned topic, as we continue to search more general, more fundamental and more precise methods of specifying it. Pauling electronegativities are based upon empirical thermodynamic data about bond energies after using a certain equation that was "picked", not derived from scratch. The values are an especially poorly characterized for shift elements, such together the $\ceCu$ in her problem. You get some not-so-easy to describe situations, like $\ceHF$ together a gas the is a borderline ionic compound.
Finally, in irradiate of this comments, the answer come your question is the bonding in $\ceCuCl_2$ (I"m pretty sure that"s what you actually expected to write) has actually intermediate characteristics between a purely ionic and a polar covalent bond, with comparable contributions (though pinpointing which is highest possible sounds choose an exercise in futility). A an excellent way to study it an ext in depth is to analysis Fajans" rules. After ~ a small self-calibration, friend can acquire a an excellent feel because that the level of ionicity and covalency of a compound.
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Some further however less specific evidence (lots that caveats!) because that the intermediate character of $\ceCuCl_2$ have the right to be found by looking at the substances" melting and also boiling clues ($\pu498°C$ and also $\pu993°C$