Sodium atom and sodium ion

Options

A. are chemically the same
B. have the same number of protons
C. have the same number of electrons
D. react spontaneously with water

Answer

### Step-by-Step Solution

1. **Understanding Sodium Atom**:
- A sodium atom is represented by the chemical symbol Na.
- It is classified as an alkali metal.
- The atomic number of sodium is 11, which means it has 11 protons and, in a neutral state, 11 electrons.

2. **Understanding Sodium Ion**:
- A sodium ion is formed when a sodium atom loses one electron.
- This loss of an electron results in a positive charge, making it a cation (specifically, Na⁺).
- The sodium ion still has 11 protons (since the atomic number remains the same), but it now has only 10 electrons.

3. **Comparison of Sodium Atom and Sodium Ion**:
- **Chemical Identity**: Sodium atom (Na) and sodium ion (Na⁺) are not chemically the same. The sodium atom can participate in chemical reactions, while the sodium ion does not react in the same way.
- **Number of Protons**: Both the sodium atom and sodium ion have the same number of protons (11).
- **Number of Electrons**: The sodium atom has 11 electrons, while the sodium ion has only 10 electrons due to the loss of one electron.
- **Reactivity with Water**: Sodium reacts with water to form sodium hydroxide (NaOH) and hydrogen gas. In contrast, the sodium ion does not react with water.

4. **Conclusion**:
- The statements regarding sodium atom and sodium ion can be summarized as follows:
- They have the same number of protons (correct).
- They do not have the same number of electrons (incorrect).
- The sodium atom reacts with water, while the sodium ion does not (incorrect).