As an electron is brought form an infinite distance close to the nucleus fo the atom the enrgy of the electron -nucleus system :

Options

A. Increased to a grater positive value
B. Decreases to a smaller positiive value
C. Decreases to a smaller positiive value
D. Increased to a grater positive value

Explanation

To solve the question regarding the energy of an electron-nucleus system as an electron is brought from an infinite distance close to the nucleus of the atom, we can follow these steps:

### Step 1: Understand the Concept of Potential Energy
When an electron is at an infinite distance from the nucleus, it has a certain amount of potential energy, which we can consider as zero for convenience. As the electron moves closer to the nucleus, the potential energy of the system changes.

**Hint:** Remember that potential energy in electrostatics is defined as zero at infinite separation between charges.

### Step 2: Analyze the Interaction Between Electron and Nucleus
The nucleus is positively charged (due to protons), and the electron is negatively charged. As the electron approaches the nucleus, the attractive force between them increases, leading to a decrease in potential energy.

**Hint:** Consider the nature of the forces involved; attractive forces will lower the potential energy of the system.

### Step 3: Determine the Change in Energy
As the electron moves closer to the nucleus, the potential energy becomes negative, indicating that energy is released in the process. The closer the electron gets to the nucleus, the more negative the potential energy becomes.

**Hint:** Recall that a negative potential energy indicates a bound system, where energy is released when the system moves to a lower energy state.

### Step 4: Conclude the Change in Energy
Since the energy of the electron-nucleus system decreases (becomes more negative) as the electron approaches the nucleus, we conclude that the energy of the system decreases.

**Hint:** Think about how energy conservation applies here; energy is released as the electron becomes bound to the nucleus.

### Final Answer
The energy of the electron-nucleus system decreases as the electron is brought from an infinite distance close to the nucleus of the atom.

**Correct Option:** C (Decreased)