Question

1. predict: ionization energy (ie) is the energy required to remove an electron from an atom. as atomic radius increases, the valence electrons get farther from the nucleus. how do you think an atoms size will affect its ability to hold on to its valence electrons? why?
2. investigate: select h. in the gizmo, the hydrogen atom is shown next to a positive charge. as you move the atom to the right, the force of attraction between the positive charge and the valence electron will increase until the electron is removed.

slowly drag the atom towards the charge. after the electron is removed, use the ruler to measure the distance between the original and the final position of the electron. record the distance and ionization energy in the table, then repeat for the other group 1 elements.

Explanation:

As atomic radius increases, the valence electrons are farther from the nucleus. According to Coulomb's law (\(F = k\frac{q_1q_2}{r^{2}}\), where \(F\) is the force of attraction, \(k\) is a constant, \(q_1\) and \(q_2\) are charges, and \(r\) is the distance between them), the force of attraction (\(F\)) between the positively - charged nucleus (\(q_1\)) and the valence electron (\(q_2\)) decreases as \(r\) (atomic radius) increases. A weaker force of attraction means the atom has a weaker hold on its valence electrons.

Answer:

As an atom's size (atomic radius) increases, its ability to hold on to its valence electrons decreases. This is because, by Coulomb's law, the force of attraction between the nucleus and valence electrons weakens with an increase in the distance (atomic radius) between them.