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According to the definition of dative bonding electrons are shared which are given by one of the atoms, so if the electrons are shared so how come there is charge on the elements in the dative bonding?

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To begin with, the term "dative bond" is not used anymore. It has been replaced by "coordinate bond" :

Let's have an example of this kind of bond.

Ammonium ion

As you can see, this kind of bond occurs when an atom is giving two electrons from itself to form the bond. The typical coordinate bond is the $\ce {N}$ already bonded with $\ce {3H}$ forming a bond with a proton. Since the proton has no electron, the $\ce {N}$ atom has to fully give one of his electron from his remaining doublet to form the bond. But to respect the charge equality, you had a positive charge at the begining, no electrons were added or removed from the system, so the positive charge should remains on the final molecular edifice.

The question is, where is located this positive charge ? One could start thinking this charge is located on the $\ce {N}$ atom since it is giving an electron. But actually, the $\ce {N}$ atom has a greater electronegativity than the $\ce {H}$ atom, that's say its hability to attract electrons is greater. Therefore the positive charge remaining should be equaly distributed over all the $\ce {4H}$ since they are equivalent.

But, altogether, the net charge of the edifice will be $+1$.

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It's formal charge - it often doesn't mean there are full charges like in zwitterions but dative bonds are usually strongly polarised.

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Dative bond/coordinate bond is a type of covalent bond where an atom donate electron and another one does not share any but receive the electron.

Note that i bolded covalent bond. Meaning that this bond happened between 2 non-metals, not between metal and non-metal (that's Ionic bond). In ionic bond there's formal charge because there's electrostatic force occuring between the two atom, but in covalent bond there is no electrostatic attraction at all.

In order to keep track between the transfer of electron we use either formal charge or oxidation number, because covalent bond doesn't have any electrostatic attraction we use oxidation number (also known as imaginary formal charge).

So what you meant might be Oxidation Number and not Formal Charge

Hope that helps.

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  • $\begingroup$ This is incorrect. There can be dative bonds between any type of atom, they usually have high covalent character. A partial charge results from the asymmetry of the nuclear charges and the electrons. There always is electrostatic interactions (which are certainly attractive) in bonds. Oxidation number, formal charge, actual charge are not really related concepts. $\endgroup$ Dec 22 '19 at 13:32

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