Which is the main negative mineral ion in extracellular fliud ?

Options

A. `SO_(4)^(2-)`
B. `Cl^(-)`
C. `NO_(3)^(-)`
D. `OH^(-)`

Answer

**Step-by-Step Solution:**

1. **Understanding Extracellular Fluid Composition**: Extracellular fluid is the body fluid located outside of cells. It primarily consists of plasma and interstitial fluid. The major ions present in extracellular fluid include sodium (Na+) and chloride (Cl-).

2. **Identifying the Main Negative Ion**: Among the ions listed in the question (CO42-, Cl-, NO3-, OH-), we need to determine which one is predominantly found in extracellular fluid.

3. **Analyzing the Options**:
- **CO42- (Carbonate Ion)**: While present, it is not the main negative ion in extracellular fluid.
- **Cl- (Chloride Ion)**: This is a major negative ion found in extracellular fluid, often paired with sodium ions.
- **NO3- (Nitrate Ion)**: This ion is less common in extracellular fluid compared to chloride.
- **OH- (Hydroxide Ion)**: This ion is present in very low concentrations and is not a primary component of extracellular fluid.

4. **Conclusion**: Based on the analysis, the main negative mineral ion in extracellular fluid is **Cl- (Chloride Ion)**.

**Final Answer**: Cl- (Chloride Ion)

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