College

How many grams of sodium fluoride are dissolved in 3.75 L of a 1.55 M solution?

[tex]NaF : 41.98 \, \text{g/mol}[/tex]

Answer :

To solve the problem, follow these steps:

1. Calculate the number of moles of sodium fluoride using the molarity formula. The formula for moles is:
[tex]$$
n = M \times V
$$[/tex]
where:
- [tex]$M = 1.55\,\text{mol/L}$[/tex] is the molarity,
- [tex]$V = 3.75\,\text{L}$[/tex] is the volume of the solution.

Substituting the values:
[tex]$$
n = 1.55\,\text{mol/L} \times 3.75\,\text{L} = 5.8125\,\text{mol}
$$[/tex]

2. Now, calculate the mass of sodium fluoride using its molar mass. The mass is found by:
[tex]$$
\text{mass} = n \times M_{\text{NaF}}
$$[/tex]
where [tex]$M_{\text{NaF}} = 41.98\,\text{g/mol}$[/tex] is the molar mass of sodium fluoride.

Substituting the number of moles and the molar mass:
[tex]$$
\text{mass} = 5.8125\,\text{mol} \times 41.98\,\text{g/mol} = 244.00875\,\text{g}
$$[/tex]

Therefore, the solution contains approximately [tex]$244.00875\,\text{g}$[/tex] of sodium fluoride.