Question

storyline 1 exam
a calcium ion is formed from a calcium atom. how do the sizes of the calcium atom and calcium ion compare to one another?
o the calcium ion is smaller than the calcium atom because the same number of protons now attract a fewer number of electrons
o the calcium ion is larger than the calcium atom because the same number of protons now attract a greater number of electrons
o the calcium ion is smaller than the calcium atom because the same number of protons now attract a greater number of electrons
o the calcium ion is larger than the calcium atom because the same number of protons now attract a fewer number of electrons

Explanation:

When an atom loses electrons to form a cation (like calcium atom losing electrons to form calcium ion), the number of protons remains the same (as it's the atomic number property). But the number of electrons decreases. Since protons attract electrons, with fewer electrons, the same number of protons can pull the remaining electrons more tightly. This leads to a smaller size for the ion compared to the atom.

Answer:

The calcium ion is smaller than the calcium atom because the same number of protons now attract a fewer number of electrons.