Mass of one atom of an element is 7.64×`10^(−23)`g. This is equal to :

Options

A. 44u
B. 46u
C. 50u
D. 0.48u

Explanation

To solve the problem, we need to find the molar mass of the element given the mass of one atom. Here are the steps to arrive at the solution:

### Step-by-Step Solution:

1. **Identify the mass of one atom**:
The mass of one atom of the element is given as \( 7.64 \times 10^{-23} \) grams.

2. **Use Avogadro's number**:
Avogadro's number (\( N_A \)) is \( 6.02 \times 10^{23} \) atoms/mole. This number tells us how many atoms are in one mole of a substance.

3. **Calculate the mass of one mole of the element**:
The mass of one mole of atoms can be calculated using the formula:
\[ \text{Mass of one mole} = \text{Mass of one atom} \times N_A \]
Substituting the values we have:
\[ \text{Mass of one mole} = (7.64 \times 10^{-23} \, \text{g}) \times (6.02 \times 10^{23} \, \text{atoms/mole}) \]

4. **Perform the multiplication**:
\[ \text{Mass of one mole} = 7.64 \times 6.02 \, \text{g} \]
\[ = 45.9968 \, \text{g} \]

5. **Round the result**:
Rounding \( 45.9968 \, \text{g} \) gives us approximately \( 46 \, \text{g} \).

6. **Express in atomic mass units (u)**:
The molar mass in grams per mole can also be expressed in atomic mass units (u). Therefore, we can say:
\[ 46 \, \text{g/mol} = 46 \, \text{u} \]

### Final Answer:
The mass of one atom of the element is equal to \( 46 \, \text{u} \).

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