After the transfer of electrons, calcium becomes an ion with a charge of:

• A. -1
• B. -2
• C. +2
• D. +1

Answer: (C)

Verified step by step guidance

1. Recall that calcium (Ca) is an element in Group 2 of the periodic table, which means it has 2 electrons in its outermost shell (valence electrons).
2. When calcium forms an ion, it tends to lose its valence electrons to achieve a stable electron configuration similar to the nearest noble gas (argon).
3. Losing 2 electrons means calcium will have 2 more protons than electrons, resulting in a positive charge of +2.
4. Therefore, the charge on the calcium ion after electron transfer is written as Ca\(^{2+}\), indicating a +2 charge.
5. This explains why calcium does not form ions with charges of -1, -2, or +1, but rather a +2 charge.