Mass of one atom of an element is `4.0X10^-24` g. This is equal to

Options

A. 2.4 u
B. 24 u
C. 0.024 u
D. 0.24 u

Answer

To solve the problem of converting the mass of one atom of an element from grams to atomic mass units (amu), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Mass**:
The mass of one atom of the element is given as:
\[ \text{Mass} = 4.0 \times 10^{-24} \text{ g} \]

2. **Know the Conversion Factor**:
We need to use the conversion factor between grams and atomic mass units. The conversion is:
\[ 1 \text{ amu} = 1.66 \times 10^{-24} \text{ g} \]

3. **Convert Grams to AMU**:
To convert the mass from grams to amu, we can use the formula:
\[ \text{Mass in amu} = \frac{\text{Mass in grams}}{\text{Mass of 1 amu in grams}} \]
Substituting the values we have:
\[ \text{Mass in amu} = \frac{4.0 \times 10^{-24} \text{ g}}{1.66 \times 10^{-24} \text{ g/amu}} \]

4. **Perform the Calculation**:
Now, we can perform the division:
\[ \text{Mass in amu} = \frac{4.0}{1.66} \approx 2.4096 \text{ amu} \]

5. **Round the Result**:
Rounding this value gives us:
\[ \text{Mass in amu} \approx 2.4 \text{ amu} \]

6. **Conclusion**:
Therefore, the mass of one atom of the element in atomic mass units is approximately:
\[ 2.4 \text{ amu} \]