Question

after the transfer of electrons, calcium becomes an ion with a charge of type here and oxygen becomes an ion with a charge of type here.

Explanation:

Step1: Analyze Calcium's Electron Configuration

Calcium (Ca) has an atomic number of 20, so its electron configuration is $1s^2 2s^2 2p^6 3s^2 3p^6 4s^2$. To achieve a stable noble gas configuration (like Argon, $1s^2 2s^2 2p^6 3s^2 3p^6$), calcium loses 2 electrons from its outermost (4s) shell. When an atom loses electrons, it becomes a cation with a positive charge equal to the number of electrons lost. So calcium loses 2 electrons, so its charge is $+2$.

Step2: Analyze Oxygen's Electron Configuration

Oxygen (O) has an atomic number of 8, with an electron configuration of $1s^2 2s^2 2p^4$. To achieve a stable noble gas configuration (like Neon, $1s^2 2s^2 2p^6$), oxygen gains 2 electrons to fill its 2p subshell. When an atom gains electrons, it becomes an anion with a negative charge equal to the number of electrons gained. So oxygen gains 2 electrons, so its charge is $-2$.

Answer:

Calcium ion charge: $+2$; Oxygen ion charge: $-2$