The formula of a salt is XCl2. The X-ion in this salt has 28 electrons. The metal X is

Responses
A NiNi
B ZnZn
C FeFe
D V

The X-ion has 28 electrons, which means it has a charge of 2- (since neutral atoms have the same number of protons and electrons).

To determine the identity of the metal X, we can look at the periodic table and find an element with 2 fewer electrons than the neutral atom.

From the periodic table, we can see that vanadium (V) has an atomic number of 23, which means its neutral atom has 23 electrons. If we remove 2 electrons from vanadium (V), we are left with 21 electrons, which is not equal to the 28 electrons in the X-ion.

Similarly, nickel (Ni) has an atomic number of 28, which means its neutral atom has 28 electrons. If we remove 2 electrons from nickel (Ni), we are left with 26 electrons, which is not equal to the 28 electrons in the X-ion.

Zinc (Zn) has an atomic number of 30, which means its neutral atom has 30 electrons. If we remove 2 electrons from zinc (Zn), we are left with 28 electrons, which matches the 28-electron count of the X-ion.

Therefore, the metal X in the salt XCl2 is Zinc (Zn), so the correct answer is B.