The characteristics of two different types of reactions are shown below: reaction a: protons are gained or lost by the atom of an element. reaction b: electrons are lost by the atoms of an element. which statement is true about the two reactions?

Valence electrons are involved in Reaction B but not in Reaction A.

The question is incomplete, the complete question is;

The characteristics of two different types of reactions are shown below: Reaction A: Protons are gained or lost by the atom of an element. Reaction B: Electrons are lost by the atoms of an element. Which statement is true about the two reactions? Their identity changes in both Reaction A and Reaction B. Their identity changes in Reaction A but not in Reaction B. Their identity changes in Reaction B but not in Reaction A. Their identity remains the same in both Reaction A and Reaction B.

Their identity changes in Reaction A but not in Reaction B

Explanation:

The identity of an atom lies in its atomic number. The atomic number of an element his the number of protons in its atom. The periodic table is arranged in order of increasing atomic number.

In reaction B, the species simply gains an electron to become a negative ion. The identity of the atom didn't change. The identity of an atom only changes when the atomic number(number of protons) changes. Hence the identity of the atom is changed in reaction A.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.