Question

Describe in detail how to prepare 500.0 mL of a 2.5 M calcium chloride solution. Calcium chloride is purchased as a solid. TO pipare weigh the deied wtight a 500.0 ml of a 2.3 M Calciom chlonde sdotion, frat

Answer 1

Answer:

In a volumetric flask of marking 500.0 mL add 138.75 grams of calcium chloride and add small amount of water to dissolve solute completely. After the solute gets completely soluble add more water up till the mark of 500 ml.

Explanation:

Concentration of calcium chloride = 2.5 M

Volume of the solution = 500.0 ml = 0.5000 L

Moles of calcium chloride = n

$c=\frac{n}{V(L)}$

n = moles of solute

c = concentration of solution

V = volume of the solution in L

$2.5 M=\frac{n}{0.5000 L}$

$n=2.5 M\times 0.5000 L = 1.2500 mol$

$n=\frac{\text{Mass of calcium chloride}}{\text{Molar mass of calcium chloride}}$

$1.2500 mol=\frac{\text{Mass of calcium chloride}}{111 g/mol}$

Mass of calcium chloride = 111 g/mol × 1.2500 mol = 138.75 g

In a volumetric flask of marking 500.0 mL add 138.75 grams of calcium chloride and add small amount of water to dissolve solute completely. After the the solute gets completely soluble add more water up till the mark of 500 ml.