# Preparation of solutions from a concentrated stock.

The only problems that need to be done are numbers (3) and (4) on the second scanned document and the question below . Numbers (1), (2), (5) are finished problems that do not need to be done so problems (3) and (4) should be done using the same format (do Calculations and preparation)as those.

Also please answer this question:

Prepare bovine serum albumin solutions (.2, .4, .6, and .8) from 1.0 mg/ml stock. Show how to do this in the same format and (1) and (2) with calculations and preparation.

https://brainmass.com/chemistry/acids-and-bases/preparation-of-solutions-from-a-concentrated-stock-113537

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3. Prepare 0.1L of 0.1M sodium hydoxide (NaOH).

NaOH usually comes in a solid so this is a simple solution to make in terms of calculations and preparations.

a) Calculations:

The molecular weight (MW) of NaOH is: 40 A 0.1M solution would 0.1 MW per liter (0.1 x 40 = 4.0g/liter). Since you are making 100ml (100ml=0.1L) you will need one-tenth of 0.1M or 0.4 g of NaOH.

b) Preparation

1. Weigh our 0.4g of NaOH on a balance.

2. Transfer the NaOH to a 100ml bottle and approximately 50ml of distilled water (dH2O).

3. Dissolve the NaOH by swirling the bottle . Once the NaOH is completely dissolved, the solution should be clear. Add more dH2O until the volume is exactly 100ml. You now have 100ml of a 0.1M solution of NaOH.

4. Prepare a 0.1L of 0.1M acetic acid.

Acetic acid is a solution that is found as a ...

#### Solution Summary

This solution outlines the steps needed to prepare a series of diluted solutions from a concentrated stock. The solution shows how to calculate the final product given a stock solution of known concentration.