Chlorine atom does not differ from the chloride ion in which of the following context?

Options

A. Electron
B. Volume
C. Proton
D. Chemical reactivity

Explanation

To solve the question "Chlorine atom does not differ from the chloride ion in which of the following context?", we will analyze the options provided and determine the correct answer step by step.

### Step 1: Understand the Composition of Chlorine Atom and Chloride Ion
- A chlorine atom (Cl) has an atomic number of 17, which means it has 17 protons and, in its neutral state, also 17 electrons.
- A chloride ion (Cl⁻) is formed when a chlorine atom gains one additional electron, resulting in 18 electrons while still having 17 protons.

**Hint:** Remember that the atomic number indicates the number of protons, and for neutral atoms, the number of electrons equals the number of protons.

### Step 2: Analyze the Options
1. **Electrons**:
- Chlorine atom has 17 electrons.
- Chloride ion has 18 electrons.
- **Conclusion**: They differ in the number of electrons.

2. **Volume**:
- The volume of an atom is related to its size. The chloride ion is larger than the chlorine atom because the added electron causes increased electron-electron repulsion.
- **Conclusion**: They differ in volume.

3. **Protons**:
- Both the chlorine atom and the chloride ion have 17 protons.
- **Conclusion**: They do not differ in the number of protons.

4. **Chemical Reactivity**:
- The chemical reactivity is influenced by the number of valence electrons. Chlorine has 7 valence electrons (configuration 2, 8, 7), while chloride has 8 valence electrons (configuration 2, 8, 8).
- **Conclusion**: They differ in chemical reactivity.

### Step 3: Identify the Correct Answer
From the analysis, the only context in which the chlorine atom does not differ from the chloride ion is in the number of protons. Therefore, the correct answer is:

**Protons (C)**

### Final Answer:
Chlorine atom does not differ from the chloride ion in the context of the number of protons.

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