Preparation of a 250 mL .25 molal solution of CaCl2

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Start date Feb 16, 2011
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Preparation

In summary, the formula for calculating the number of moles in a solution is moles = (mass of solute in grams) / (molar mass of solute in grams/mol). To prepare a 250 mL .25 molal solution of CaCl2, you will need to dissolve 15.5 grams of CaCl2 in 250 mL of water. The resulting solution will have a concentration of .25 molal, containing .25 moles of CaCl2 for every kilogram of water. The molar mass of CaCl2 is 110.98 grams/mol. Any type of water can be used to prepare this solution, but it is recommended to use distilled or deionized water to ensure accuracy.

Feb 16, 2011

TypeFun

Homework Statement

Describe in detail how you would prepare 250 mL of a .25 molal solution of CaCl₂

Homework Equations

CaCl₂: 110.98 g/mol

molality = #moles of solute/kg of solvent

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Feb 21, 2011

Borek

Mentor

You need to find solution density in tables to solve the problem.

1. What is the formula for calculating the number of moles in a solution?

The formula for calculating the number of moles in a solution is moles = (mass of solute in grams) / (molar mass of solute in grams/mol).

2. How do I prepare a 250 mL .25 molal solution of CaCl2?

To prepare a 250 mL .25 molal solution of CaCl2, you will need to dissolve 15.5 grams of CaCl2 in 250 mL of water. This will result in a solution with a concentration of .25 molal, meaning it contains .25 moles of CaCl2 for every kilogram of water in the solution.

3. What is the molar mass of CaCl2?

The molar mass of CaCl2 is 110.98 grams/mol.

4. Can I use any type of water to prepare this solution?

Yes, you can use any type of water to prepare this solution. However, it is recommended to use distilled or deionized water to avoid any impurities that may affect the accuracy of the solution's concentration.

5. What is the purpose of preparing a .25 molal solution of CaCl2?

A .25 molal solution of CaCl2 can be used in various scientific experiments and processes, such as in chemistry labs for precipitating proteins, in medicine for electrolyte replacement, and in industrial processes for producing calcium chloride.