The number of atoms in 2.5mole of Na are?

Options

A. 15 x `10^23`
B. 21 x `10^23`
C. 25 x `10^23`
D. 23 x `10^23`

Explanation

To find the number of atoms in 2.5 moles of sodium (Na), we can follow these steps:

### Step 1: Understand the relationship between moles and atoms
We know that 1 mole of any substance contains Avogadro's number of particles (atoms, molecules, etc.). Avogadro's number is approximately \(6.02 \times 10^{23}\).

### Step 2: Calculate the number of atoms in 2.5 moles
To find the number of atoms in 2.5 moles of sodium, we can use the formula:
\[ \text{Number of atoms} = \text{Number of moles} \times \text{Avogadro's number} \]
Substituting the values:
\[ \text{Number of atoms} = 2.5 \, \text{moles} \times 6.02 \times 10^{23} \, \text{atoms/mole} \]

### Step 3: Perform the multiplication
Now, we multiply:
\[ 2.5 \times 6.02 = 15.05 \]
So,
\[ \text{Number of atoms} = 15.05 \times 10^{23} \, \text{atoms} \]

### Step 4: Express in scientific notation
We can express \(15.05\) in scientific notation:
\[ 15.05 \times 10^{23} \, \text{atoms} = 1.505 \times 10^{24} \, \text{atoms} \]

### Final Answer
Thus, the number of atoms in 2.5 moles of sodium is approximately \(1.505 \times 10^{24}\) atoms.

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