Mass of one atom of the element `A` is `3.9854 xx 10^(-23)g`. How many atoms are contained in 1g of the element `A` ?

Options

A. `2.509xx120^(23)`
B. `6.022xx10^(23)`
C. `12.044xx10^(23)`
D. None of these

Answer

To find out how many atoms are contained in 1 gram of the element A, we can follow these steps:

### Step 1: Identify the mass of one atom
We are given that the mass of one atom of element A is \(3.9854 \times 10^{-23}\) grams.

### Step 2: Determine how many atoms are in 1 gram
To find the number of atoms in 1 gram of element A, we can use the formula:

\[ \text{Number of atoms} = \frac{\text{Total mass}}{\text{Mass of one atom}} \]

In this case, the total mass is 1 gram.

### Step 3: Substitute the values into the formula
Substituting the values we have:

\[ \text{Number of atoms} = \frac{1 \text{ gram}}{3.9854 \times 10^{-23} \text{ grams/atom}} \]

### Step 4: Perform the calculation
Now, we perform the calculation:

\[ \text{Number of atoms} = \frac{1}{3.9854 \times 10^{-23}} \approx 2.51 \times 10^{22} \text{ atoms} \]

### Step 5: Round the answer
Rounding the answer to three significant figures, we get:

\[ \text{Number of atoms} \approx 2.50 \times 10^{22} \text{ atoms} \]

### Final Answer
Thus, the number of atoms contained in 1 gram of the element A is approximately \(2.50 \times 10^{22}\) atoms.

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