Read the following chemical equation.

mg(s) + h+ cl− → mg2+ cl− + h2

what most likely happens during this reaction?
magnesium gains two electrons.
magnesium loses two electrons.
chlorine gains one electron.
chlorine loses one electron.

Answer

Hi,

In this equation, i see we have two answers;

B. Magnesium loses two electrons

C. Chlorine gains one electron

Explanation

Due to their valences, Magnesium,Mg+2 and Chlorine -1, magnesium atom will loose two electrons to form a stable state 2+ ions.Chlorine as a member of group 7 elements of the periodic table, the chlorine atom will gain 1 electron to form a stable 1- ion and facilitate the formation of the ionic bond that occurs between the two elements.

Magnesium loses two electrons

Step-by-step explanation:

The balanced equation is  

Mg + 2H⁺ + 2Cl⁻ ⟶ Mg²⁺ + 2Cl⁻ + H₂

Mg loses two electrons because it becomes Mg²⁺:

Mg ⟶Mg²⁺ + 2e⁻

C and D are both wrong, because Cl⁻ neither gains nor loses electrons. It is Cl⁻ at the beginning and Cl⁻ at the end of the reaction, so it is a spectator ion.

The substance that gains electrons is H⁺:

2H⁺ + 2e⁻ ⟶ H₂

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."