In the following questions, a statement I is given and a corresponding statement II follows it. Mark the correct answer as:

Statement I: Properties of atom and its corresponding ions remain same.

Statement II: Electron configuration of atom and ion are different.

If statement I is false but statement II is true.

The correct answer is option 4. If statement I is false but statement II is true.

Let us delve into why the correct answer is that statement I is false but statement II is true.

Statement I: Properties of atom and its corresponding ions remain the same.

Atomic Properties: The properties of an atom are determined by its electron configuration, size, ionization energy, electronegativity, and other factors.

Ionic Properties: When an atom gains or loses electrons to form an ion, its electron configuration changes, which in turn alters its chemical and physical properties.

Sodium (Na): A neutral sodium atom has the electron configuration \(1s^2 2s^2 2p^6 3s^1\). Sodium is a highly reactive metal.

Sodium Ion (\(Na^+\)): The sodium ion has the electron configuration \(1s^2 2s^2 2p^6\), which is stable and resembles the electron configuration of neon (Ne), a noble gas. The \(Na^+\) ion is not reactive like the neutral sodium atom.

Therefore, the properties of the atom and its corresponding ion are different, making statement I false.

Statement II: Electron configuration of atom and ion are different.

Electron Configuration: When an atom forms an ion, it either loses or gains electrons, leading to a change in its electron configuration.

Chlorine (Cl): A neutral chlorine atom has the electron configuration \(1s^2 2s^2 2p^6 3s^2 3p^5\).

Chloride Ion (\(Cl^-\)): The chloride ion has the electron configuration \(1s^2 2s^2 2p^6 3s^2 3p^6\), having gained one electron to complete its valence shell, making it isoelectronic with argon (Ar).

Since the electron configurations of the atom and the ion are indeed different, statement II is true.

Combining the analyses:

Statement I is false because the properties of atoms and their corresponding ions are not the same.

Statement II is true because the electron configurations of atoms and ions are different.

Thus, the correct answer is: 4. If statement I is false but statement II is true.