How many moles are in 19.6 g of Sodium (Na)? What is the conversion factor?
The Correct Answer and Explanation is:
To calculate the number of moles in 19.6 grams of sodium (Na), you need to use the formula for converting grams to moles:
[
\text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}}
]
Step 1: Identify the molar mass of sodium (Na)
The molar mass of sodium is approximately 22.99 g/mol. This value indicates that one mole of sodium weighs about 22.99 grams.
Step 2: Calculate the number of moles
Using the formula, we can calculate the moles of sodium in 19.6 grams:
[
\text{Number of moles} = \frac{19.6 \, \text{g}}{22.99 \, \text{g/mol}} \approx 0.854 \, \text{moles}
]
Conversion Factor
The conversion factor from grams to moles for sodium can be derived from its molar mass. It can be expressed as:
[
1 \, \text{mol Na} = 22.99 \, \text{g Na}
]
This conversion factor allows us to convert any mass of sodium to moles or vice versa.
Explanation
Understanding how to convert grams to moles is fundamental in chemistry, particularly in stoichiometry, where the relationships between different substances in a chemical reaction are quantified. The concept of the mole provides a bridge between the atomic scale and the macroscopic scale of substances. A mole is defined as (6.022 \times 10^{23}) particles (atoms, molecules, etc.), known as Avogadro’s number.
When you have a specific mass of a substance, knowing its molar mass allows you to convert that mass into moles. This is essential for calculations involving chemical reactions, as it allows chemists to determine how much of each reactant is needed and how much product will be formed. In practical applications, this calculation is crucial for mixing precise amounts of chemicals for reactions, ensuring safety, and achieving desired yields in laboratory and industrial settings.
In conclusion, 19.6 grams of sodium is approximately 0.854 moles, illustrating the importance of molar mass in quantitative chemical analysis.