Metal x combines with fluorine to form XF2. what compound does it form with the sulfate ion? A. XSO4
B. X2SO4
C. X(SO4)2

Explanation:

The answer is A b/c

the polyatomic SO4² have 2 valance electron,also

the metal X also have 2 valance electron so,They cancel each other

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.