Answer:
The concentration of the solution is 2.86 M
Explanation:
Molarity is a unit of concentration based on the volume of a solution. It is defined as the number of moles of solute that are dissolved in a given volume. In other words, molarity is defined as the number of moles of solute per liter of solution.
The Molarity of a solution is determined by the following expression:
![Molarity (M)=\frac{number of moles of solute}{Volume}](https://tex.z-dn.net/?f=Molarity%20%28M%29%3D%5Cfrac%7Bnumber%20of%20moles%20of%20solute%7D%7BVolume%7D)
Molarity is expressed in units (
).
In this case, you must then know the number of moles of HF, for which you must know the molar mass. Being:
the molar mass of HF is: HF= 1 g/mole + 19 g/mole= 20 g/mole
Then the following rule of three applies: if 20 g of HF are available in 1 mole, 14.3 g in how many moles will they be?
![moles=\frac{14.3 g*1 mole}{20 g}](https://tex.z-dn.net/?f=moles%3D%5Cfrac%7B14.3%20g%2A1%20mole%7D%7B20%20g%7D)
moles= 0.715
So:
- number of moles of solute: 0.715 moles
- Volume: 250 mL=0.250 L (being 1 L=1000 mL)
Replacing:
![Molarity=\frac{0.715 moles}{0.250 L}](https://tex.z-dn.net/?f=Molarity%3D%5Cfrac%7B0.715%20moles%7D%7B0.250%20L%7D)
Solving:
Molarity= 2.86
=2.86 M
<u><em>The concentration of the solution is 2.86 M</em></u>