Answer:
82.416 g of KNO ₃ is needed to produce 510.0 mL of a 1.6 M KNO ₃ solution.
Explanation:
Since molarity is the number of moles of solute that are dissolved in a given volume, calculated by dividing the moles of solute by the volume of the solution, the following rule of three can be applied: if in 1 L (1,000 mL) of KNO₃ there are 1.6 moles of the compound present, in 510 mL how many moles will there be?
[tex]moles=\frac{510 mL*1.6 moles}{1000 mL}[/tex]
moles= 0.816
Being the molar mass of the elements:
So the molar mass of the compound KNO₃ is:
KNO₃= 39 g/mole + 14 g/mole + 3*16 g/mole= 101 g/mole
Now I can apply the following rule of three: if in 1 mole of KNO₃ there are 101 g, in 0.816 moles how much mass is there?
[tex]mass=\frac{0.816 moles*101 grams}{1 mole}[/tex]
mass= 82.416 grams
82.416 g of KNO ₃ is needed to produce 510.0 mL of a 1.6 M KNO ₃ solution.
