Question 6

The atom has gained an electron and now has a net negative charge.

The symbol "–" in Cl⁻ indicates that the chlorine atom has gained an electron, resulting in an overall negative charge.

A) The atom has gained a proton and now has a net positive charge.

This option is incorrect because gaining a proton would increase the positive charge of the atom, leading to a cation rather than an anion. Chlorine gaining a proton would not correspond with the notation Cl⁻.

B) The atom has lost an electron and now has a net positive charge.

This option is also incorrect. Losing an electron would result in a positive charge, which is not represented by Cl⁻. Instead, Cl⁻ shows that the atom has a surplus of electrons, not a deficit.

C) The atom has gained an electron and now has a net negative charge.

This statement is correct. The "–" indicates that the chlorine atom has acquired an additional electron, giving it a negative charge, and thus it is represented as Cl⁻.

D) The atom has lost a proton and now has a net negative charge.

This option is incorrect because protons are not typically lost in chemical reactions; rather, they define the element's identity. Losing a proton would not create a negative charge in the context of atomic notation.

Conclusion

The correct answer, C, clearly explains that the addition of an electron results in a negative charge, which is the essence of the Cl⁻ notation. All other options misinterpret the concept of charge and the behavior of electrons and protons in atomic structure. Therefore, C is definitively the right choice as it accurately reflects the meaning of the notation used.