Question

Calculate the molarity of a solution made by 1,5kg of K. CO₂ in 850 mL of water.

Answer 1

Answer:

17.83M

Explanation:

Given parameters:

Mass of KCO₂ = 1.5kg

Volume of water  = 850mL

Unknown:

Molarity of solution  = ?

Solution:

Molarity is defined as the number of moles per unit volume. It is the number of moles of solute in a given volume of solution.

   Molarity  = $\frac{number of moles }{volume}$

Number of moles of solute  = $\frac{mass of KCO_{2} }{molar mass}$

  Molar mass of KCO₂  = 39 + 12 + 3(16) = 99g/mol

  Number of moles  = $\frac{1500}{99}$   = 15.15moles

   850mL : gives 0.85L

     

Molarity  = $\frac{15.15}{0.85}$   = 17.83M