Question

Which explains the charge of an ion of calcium (Ca)?

A. 2 electrons are gained by the atom.
B. 2 electrons are removed from the atom.
C. 2 protons are removed from the atom.
D. 2 protons are gained by the atom.

Answer 1

Answer:

The correct option is B. 2 electrons are removed from the atom.

Step-by-step explanation:

Calcium (Ca) has an atomic number of 20, which means it has 20 electrons in its neutral state, arranged in shells around the nucleus. The electronic configuration of neutral calcium is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s².

When calcium loses two electrons from its outermost shell (4s²), it forms a calcium ion (Ca²⁺) with a noble gas electron configuration of argon. This is achieved by removing the two valence electrons from the 4s² subshell. The loss of two electrons from the neutral calcium atom leaves behind 18 electrons, but still 20 positively charged protons in the nucleus, giving the calcium ion a 2+ charge.

Answer 2

B. 2 electrons are removed from the atom

Step-by-step explanation:

The charge of an ion of calcium (Ca) is +2, which means that the calcium atom has lost 2 electrons.

Therefore, the correct answer is B. 2 electrons are removed from the atom.