What is false for mole fraction

Options

A. `Xlt1`
B. `-2lt=Xlt=2`
C. `0lt=Xlt=1`
D. Always non negative

Answer

To solve the question "What is false for mole fraction?", we need to analyze the properties of mole fraction and evaluate the given options.

### Step-by-Step Solution:

1. **Understanding Mole Fraction**:
- The mole fraction (X) of a component in a mixture is defined as the ratio of the number of moles of that component to the total number of moles of all components in the mixture.
- Mathematically, for a component X in a mixture of X and Y, the mole fraction is given by:
\[ X = \frac{\text{moles of X}}{\text{moles of X} + \text{moles of Y}} \]

2. **Evaluating the Options**:
- **Option A**: "X is less than 1"
- This is true because the mole fraction is a ratio of the number of moles of one component to the total number of moles, which will always yield a value less than 1.

- **Option B**: "X should be -2 to 2"
- This is false. The mole fraction cannot be negative, as it represents a ratio of moles, which cannot be negative. Therefore, this option is incorrect.

- **Option C**: "X ranges from 0 to 1"
- This is true. The mole fraction can take values from 0 (when there are no moles of that component) to 1 (when the component is the only one present).

- **Option D**: "Always non-negative"
- This is true. Since mole fractions are derived from the number of moles, which cannot be negative, mole fractions are always non-negative.

3. **Conclusion**:
- The only false statement regarding mole fraction is **Option B**: "X should be -2 to 2".

### Final Answer:
The false statement regarding mole fraction is **Option B**: "X should be -2 to 2".