Question

Atom $\mathit{A}$is easier to polarize than atom $\mathit{B}$. Which atom, $\mathit{A}$or $\mathit{B}$, would experience a greater attraction to a point charge a distance $\mathit{r}$away? Explain your reasoning.

Short answer

Atom A will have greater attraction than atom B as atom A has greater polarization.

Step-by-step solution

Significance of Polarization of atom

Polarization of an atom occurs when there is a deformation of an atom or group of atoms in a molecule in the presence of an electrical field around the atom.

Explanation of greater attraction to a point charge

Atomic polarization occurs when an atom is placed in the external electrical field, there is deformation that occurs in the atom due to the size of the atom becoming larger. Therefore, due to the bigger size of an atom, the distance between the point charge and an atom decreases. When the distance between the atom and point charge decreases, this will lead to a high attractive force.

As atom A is easily polarized, which is an induced dipole, it produces an electric field at the point charge’s location.

Here, the force on the electric field is equal to the magnitude of the electric field that happens due to polarization.

The equation of the magnitude of the electric field and the force is expressed as:

$$\begin{gathered} E_2=k^2\left(\frac{2\propto Q}{r^5}\right) \\ =F_2 \end{gathered}$$

Here, $k$is the electric field constant, $\propto$is the polarization,$Q$ is the charge, and the distance.

As the force is directly proportional to the polarization, atom A has greater polarization, and the attraction force is also higher.

Atom A is easy to polarize; therefore, the polarizing ability of atom A is greater than atom B, and due to its high polarizing ability, the strength of attractive forces between atom A and a point charge at a distance r will also increase.

Thus, atom A would have greater attraction than atom B as atom A has greater polarization.