Question

When an atom gains an electron to achieve stability, it becomes ___________ charged (answer is "negatively" or "positively." What happens to an atom’s charge if it loses (donates) an electron? (hint: all atoms start out electrically neutral because the # of protons = # of electrons)

Answer 1

Answer: When an atom gains an electron to achieve stability, it becomes negatively charged. The charge on an atom becomes positive when it loses (donates) an electron.

Explanation:

When a neutral atom tends to lose an electrons then due to decrease in number of electrons holded by the atom there will occur a positive charge on the atom. For example, electronic distribution of calcium is 2, 8, 8, 2.

So, in order to attain stability it will lose its 2 valence electrons and hence becomes $Ca^{2+}$ ion.  

This also means that charge on the atom increases. And, when a neutral atom loses an electron then due to increase in number of electrons into the atom there will occur a negative charge on the atom.

For example, electronic distribution of oxygen is 2, 6. To attain stability it will gain 2 electrons and hence, it formed $O^{2-}$ ion.

Thus, we can conclude that when an atom gains an electron to achieve stability, it becomes negatively charged. The charge on an atom becomes positive when it loses (donates) an electron.