Question

Shameeka is studying for an exam. She took the notes below about calcium and chlorine, which are known to form ionic bonds.

Calcium, which is a metal, donates 2 electrons to chlorine.
The individual calcium atoms become ions with a negative 2 charge.
The bond between calcium and chlorine makes the atoms stable.
Calcium and chlorine attract each other.

Which best describes Shameeka’s error?

Calcium is a metal, so it donates protons, not electrons.
The individual calcium atom has a positive, not negative, 2 charge.
The bond formed makes the atoms unstable, not stable.
Calcium and chlorine repel, not attract, each other.

Answer 1

"The individual calcium atom has a positive, not negative, 2 charge."

Explanation: Calcium (a metal) loses two electrons to form Ca2+ (a positive ion). Chlorine atoms each gain an electron to become Cl−. The resulting Ca2+ and Cl− ions attract and form a stable ionic compound (calcium chloride). The other choices are incorrect: metals donate electrons (not protons), ionic bonding makes atoms more stable, and opposite charges attract (not repel).