Calculate the molality of an aqueous solution that is 20.1% by mass calcium chloride. you might need to know that the density is

Question

2 years ago

15

1.20 g/ml

2 answers:

timama [110] · Answer 1 · 2023-12-11T11:39:07+03:00

4 0

This is math not english recategorize this plz

Charra [1.4K] · Answer 2 · 2023-12-11T13:08:38+03:00

The molarity of an aqueous solution that is 20.1 % by mass calcium chloride is 2.755 M

<h2>Further Explanation:</h2><h3>Molarity </h3>

Molarity may be defined as the concentration of a solution in moles per liter. It is calculated by dividing the number of moles of a solution, n by its volume in liters, V.
That is; Molarity = n/V, where n is the number of moles and V is the volume in liters.
Therefore; when given the molarity of a solution and the volume of the solution, then we can get the number of moles, by multiplying the molarity by volume;

Number of moles = Molarity x Volume

Additionally, the number of moles of a compound or an element can also be calculated by dividing the mass of the compound by its relative molecular mass.

In this case;

Assuming the sample of solution is 100.0 g by mass

<h3>Step 1: Mass of the solvent </h3>

Mass of the solute = 20.1/100 x (100 g)

= 20.1 g

Mass of solution = mass of solute + mass of solvent

Mass of solvent = 100 g - 20.1 g

= 79.9 g

<h3>Step 2: Volume of the solvent </h3>

Density = 1.2 g/ml

But; volume = mass/density

= 78.9 g/1.2 g/ml

= 65.75 ml or 0.06575 L

<h3>Step 3: Moles of the solute, Calcium chloride </h3>

Mass of solute = 20.1 g

But 1 mole CaCl2 = 110.98 g/mol

Therefore;

Number of moles = 20.1 g/ 110.98 g/mol

= 0.1811 moles

<h3>Step 4: Molarity of CaCl2 </h3>

Molarity = Number of moles/ Volume in L

= 0.1811 moles/ 0.06575 L

= 2.755 Mole/Liter

= 2.755 M

Keywords: Molarity, Moles, Volume

<h3>Learn more about: </h3>

Level: High School

Subject: Chemistry

Chapter: Mole and stoichiometry equations