Calculate the number of moles in `5.75 g` of sodium. `("Atomic mass of sodium" = 23)`

Explanation

To calculate the number of moles in 5.75 g of sodium, we can follow these steps:

### Step 1: Identify the formula for calculating moles
The formula to calculate the number of moles (n) is given by:
\[ n = \frac{W}{M} \]
where:
- \( n \) = number of moles
- \( W \) = mass of the substance (in grams)
- \( M \) = molar mass of the substance (in g/mol)

### Step 2: Substitute the known values
In this case, we have:
- Mass of sodium (\( W \)) = 5.75 g
- Molar mass of sodium (\( M \)) = 23 g/mol

Now, we can substitute these values into the formula:
\[ n = \frac{5.75 \, \text{g}}{23 \, \text{g/mol}} \]

### Step 3: Perform the calculation
Now, we will calculate the number of moles:
\[ n = \frac{5.75}{23} \]

Calculating this gives:
\[ n = 0.25 \, \text{moles} \]

### Final Answer
The number of moles in 5.75 g of sodium is **0.25 moles**.

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