What will be the mass of one `.^(12)C` atom in `g`?

Explanation

To find the mass of one carbon-12 atom in grams, we can follow these steps:

### Step 1: Understand the molecular weight of carbon-12
The molecular weight of carbon-12 is given as 12 grams per mole. This means that one mole of carbon-12 (which contains Avogadro's number of atoms) weighs 12 grams.

### Step 2: Identify Avogadro's number
Avogadro's number (\(N_a\)) is \(6.022 \times 10^{23}\) atoms/mole. This is the number of atoms in one mole of any substance.

### Step 3: Set up the relationship
We know that:
- 1 mole of carbon-12 = 12 grams
- 1 mole of carbon-12 = \(6.022 \times 10^{23}\) atoms

### Step 4: Calculate the mass of one carbon-12 atom
To find the mass of one carbon-12 atom, we can use the formula:

\[ \text{Mass of one atom} = \frac{\text{Mass of one mole}}{N_a} \]

Substituting the known values:

\[ \text{Mass of one carbon-12 atom} = \frac{12 \text{ grams}}{6.022 \times 10^{23} \text{ atoms}} \]

### Step 5: Perform the calculation
Now, we can calculate the mass:

\[ \text{Mass of one carbon-12 atom} = \frac{12}{6.022 \times 10^{23}} \approx 1.99 \times 10^{-23} \text{ grams} \]

### Final Answer
The mass of one carbon-12 atom is approximately \(1.99 \times 10^{-23}\) grams.

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