shine at freshly cut sodium is because of

Options

A. Oscillations of free electrons
B. Weak metallic bonding
C. Absorption of light in crystal lattice
D. Pressence of free valency at the surface

Answer

To understand why freshly cut sodium exhibits a shiny appearance, we can break down the explanation into a series of steps:

### Step-by-Step Solution:

1. **Nature of Sodium**: Sodium is an alkali metal, which is known for being soft and can be easily cut with a knife. This property is due to its metallic structure.

**Hint**: Remember that alkali metals are soft and have low melting points.

2. **Electronic Configuration**: The outermost electronic configuration of sodium is \(3s^1\). This means that sodium has one electron in its outermost shell, which is loosely bound to the nucleus.

**Hint**: Focus on the electronic configuration of sodium and how it relates to its reactivity.

3. **Free Electrons**: When sodium is freshly cut, the surface exposes free electrons. These electrons can move freely and oscillate.

**Hint**: Think about how free electrons contribute to the properties of metals.

4. **Oscillation of Electrons**: The oscillation of these free electrons leads to the emission of light. When light hits the surface of freshly cut sodium, these oscillating electrons reflect the light, giving sodium its shiny appearance.

**Hint**: Consider how light interacts with materials at the atomic level.

5. **Reactivity of Sodium**: Freshly cut sodium is highly reactive and quickly reacts with oxygen in the air to form sodium oxide (\(Na_2O\)). This reaction dulls the surface, causing the shiny appearance to fade quickly.

**Hint**: Remember that the reactivity of sodium is a key factor in the duration of its shine.

6. **Conclusion**: The shine at freshly cut sodium is primarily due to the oscillation of free electrons, which reflects light.

**Hint**: Summarize the key points to reinforce your understanding.

### Final Answer:
The shine at freshly cut sodium is because of the oscillation of free electrons on its surface, which reflects light.