The chemical symbol for the element calcium is ca. what would be the symbol representing calcium atoms that have lost two electrons? ca– ca+ ca–2 ca+2

Answer is: the symbol is Ca⁺².

Electron configuration of calcium atom: ₂₀Ca 1s² 2s² 2p⁶ 3s² 3p⁶ 4s².

Atomic number of calcium is 20, it means that it has 20 protons and 20 eletrons, so atom of calcium is neutral.

When calcium lost two electrons, it will have 20 protons (positive charge) and 18 electrons (negative charge), which means it has two protons more and it has +2 oxidation number.

Electron configuration of calcium cation: ₂₀Ca²⁺ 1s² 2s² 2p⁶ 3s² 3p⁶.