To prepare 500 mL of a 1 M BaCl₂·2H₂O solution, you'll need to follow these steps:

Step 1: Calculate the required mass of BaCl₂·2H₂O

The formula for molarity (M) is:

$\text{Molarity (M)} = \frac{\text{moles of solute}}{\text{volume of solution in liters}}$

Given:

• Desired Molarity (M) = 1 M
• Volume of solution = 500 mL = 0.5 L
• Molar mass of BaCl₂·2H₂O = 244 g/mol

First, calculate the moles of BaCl₂·2H₂O needed:

$\text{Moles of BaCl}_2·2H_2O = 1 \, \text{M} \times 0.5 \, \text{L} = 0.5 \, \text{moles}$

Now, calculate the mass of BaCl₂·2H₂O required:

$\text{Mass} = \text{moles} \times \text{molar mass} = 0.5 \, \text{moles} \times 244 \, \text{g/mol} = 122 \, \text{g}$

Step 2: Weigh the BaCl₂·2H₂O

Using a balance, carefully weigh out 122 grams of solid BaCl₂·2H₂O.

Step 3: Dissolve the BaCl₂·2H₂O in water

1. Transfer the weighed BaCl₂·2H₂O to a 500 mL volumetric flask.
2. Add distilled water to the flask gradually, swirling the flask to dissolve the BaCl₂·2H₂O completely.
3. Continue adding water until the solution reaches the 500 mL mark on the flask.

Step 4: Mix the solution

Once the BaCl₂·2H₂O is completely dissolved and the solution is at the desired volume, cap the flask and invert it several times to ensure thorough mixing.

Step 5: Label the solution

Label the flask with the concentration of the solution (1 M BaCl₂·2H₂O) and the date of preparation.

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Would you like to go over any specific step in more detail?

Here are five related questions:

1. What is the purpose of using distilled water in solution preparation?
2. How would you prepare a 0.1 M solution instead of a 1 M solution?
3. What are the potential sources of error in this preparation process?
4. How would you store the prepared solution to ensure its stability?
5. Can you explain how to prepare a solution if only a smaller amount, such as 100 mL, is needed?

Tip: Always ensure that the solid is completely dissolved before making up to the final volume to avoid concentration errors.