The formula of a salt is xcl2. the x-ion in this salt has 28 electrons. the metal x is a) ni b) zn c) fe d) v

 If the formula is XCl2, the X ion has a charge of +2 since each Cl ion has a charge of -1.  

Then if the X ion has 28 electrons with a charge of +2, it must have 30 protons.  

Its atomic number is 30, which makes it zinc. The metal X is Zn. Choice b is correct.

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