Question

What is the molarity of a solution containing 3.6 mol of KCl in 750 mL?

Answer 1

Answer:

$\boxed {\boxed {\sf 4.8 \ M \ KCl}}$

Explanation:

The molarity of a solution is found by dividing the moles of solute by the liters. of solvent.

$molarity=\frac{moles}{liters}$

We know the solution has 3.6 moles of potassium chlorine. We know there are 750 milliliters of solvent, but we need to convert this to liters.

• 1 liter is equal to 1000 milliliters. Set up a proportion.

• $\frac {1 \ L }{1000 \ mL}$

• Multiply by 750 mL and the units of mL will cancel.

• $750 \ mL * \frac {1 \ L }{1000 \ mL} = \frac {750 \ mL}{1000 \ mL}= 0.75 \ L$

Now we know the moles and liters, so we can calculate molarity.

• moles= 3.6 mol KCl
• liters= 0.75 L

Substitute these values into the formula.

$molarity= \frac{3.6 \ mol \ KCl}{0.75 \ L}$

Divide.

$molarity= 4.8 \ mol \ KCl/ L$

• 1 mole per liter is equal to 1 molar.
• Our answer of 4.8 moles of potassium chloride per liter is equal to 4.8 M KCl

$molarity= 4.8 \ M \ KCl$

The molarity of the solution is 4.8 M KCl.