Es -
the formula of a salt is xcl. the x-ion in this salt has 28 electrons. the metal x is

The metal is Copper(Cu) and the ion is

Explanation:

The given compound is XCl.

As the compound is saild to be a salt,Oxidation state of chlorine in the salt= -1(Oxidation state of Cl in all salts = -1)

Concept:

Oxidation state of a compound is zero(Sum of Oxidation states of all its atoms).

Now let the Oxidation state of X be x,

Using the concept,

Oxidation state of X + Oxidation state of Cl = 0

x + (-1) = 0

x = +1;

Therefore Oxidation state of X = +1,

So X lost 1 electron to form the compound XCl,

So, we can say that X originally had 29 electrons.

The only element in the periodic table with 29 electrons in the ground state is Copper(Cu).

i think they are all correct

explanation:

they seem good

a electromagnetic waves