Describe the preparation of 500mls of 10% formalin from a stock solution of concentration of 40% .
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Answer:
it is bio not chm so don't ask question
Answer:
Theoretically, preparing a 10% formalin solution involves diluting a 37-40% formalin solution with distilled water to obtain a solution containing 10% formaldehyde by volume. The steps involved in the preparation of a 10% formalin solution are as follows:
1) Calculate the volume of formalin and distilled water needed: To make a 100 mL 10% formalin solution, you will need 10 mL of formalin (37-40%) and 90 mL of distilled water.
2) Add formalin to a clean and dry measuring cylinder: Measure 10 mL of formalin using a clean and dry measuring cylinder.
3) Add distilled water to the measuring cylinder: Add 90 mL of distilled water to the measuring cylinder containing formalin.
4) Mix the solution: Mix the solution thoroughly using a stirring rod or by inverting the measuring cylinder several times.
5) Label the solution: Label the solution as "10% formalin" and include the date of preparation.
Numerically, the calculation for preparing a 10% formalin solution is as follows:
To make a 100 mL 10% formalin solution, you will need:
10 mL of 37-40% formalin solution
90 mL of distilled water
The formula for calculating the volume of each component needed to prepare a desired volume of a certain percentage solution is:
Volume of component (mL) = (Percentage/100) x Desired volume (mL)
Using this formula, we can calculate the volume of formalin and distilled water needed as follows:
Volume of formalin = (10/100) x 100 = 10 mL
Volume of distilled water = (90/100) x 100 = 90 mL
Therefore, to prepare a 100 mL 10% formalin solution, we need 10 mL of formalin and 90 mL of distilled water.
Explanation: