Number of atoms of He in 100 amu of He is :

Options

A. 25
B. 100
C. 50
D. `100 xx 6 xx 10^(-23)`

Answer

To determine the number of atoms of helium (He) in 100 amu of helium, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Given Data**:
- We are given a mass of helium = 100 amu (atomic mass units).
- The atomic mass of helium (He) = 4 amu.

2. **Use the Formula for Number of Atoms**:
- The number of atoms can be calculated using the formula:
\[ \text{Number of atoms} = \frac{\text{Mass of substance (in amu)}}{\text{Atomic mass (in amu)}} \]

3. **Substitute the Values**:
- Substitute the given values into the formula:
\[ \text{Number of atoms} = \frac{100 \text{ amu}}{4 \text{ amu}} \]

4. **Perform the Calculation**:
- Calculate the number of atoms:
\[ \text{Number of atoms} = \frac{100}{4} = 25 \]

5. **Conclusion**:
- Therefore, the number of atoms of helium in 100 amu of helium is **25 atoms**.

### Final Answer:
The number of atoms of He in 100 amu of He is **25 atoms**.