Protective eye goggles Gloves 100 percent isopropil alcohol Water Calculator 500 mL graduated cylinder maker Glass stirring stick
creating dilutions reduces the concentration the one liquid v the enhancement of another. In order to develop 70 percent isopropyl alcohol, a equipment of isopropil alcohol through a concentration better than 70 percent must be diluted by a calculated amount of water. The formula because that this calculation is C1_V1=C2_V2, whereby C1 and V1 is the starting concentration and also volume the the solution and C2 and also V2 is the last concentration and volume that the dilution. Because that the function of this example, the initial equipment is 100 percent isopropyl alcohol, producing a last volume of 500 mL of 70 percent isopropil alcohol.

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Identify the early concentration that the 100 percent isopropyl alcohol, which is the C1 change in the equation. The change C1=100.

Determine the preferred concentration and also volume the the final solution to obtain C2 and also V2. In this instance the last concentration C2 is 70 percent and also final volume V2 500 mL; for this reason C2=70 and also V2=500.

Solve the equation C1_V1=C2_V2 because that the unknown variable of V2. Substitute well-known variables: 100_V1=70_500, V1=35000/100, V1= 350. The is established that 350 mL that 100 percent alcohol is necessary for the preparation.


Add 350 mL the 100 percent isopropil alcohol to a 500 mL i graduated cylinder. Ensure the the measure up is read at eye level through the meniscus, the bottom of the curved liquid, in ~ 350 mL.

Add an additional 150 mL the water come the graduated cylinder because that a complete volume of 500 mL, again measured at eye level.

Pour continuing to be solution right into a new beaker significant 70 percent isopropil alcohol and stir through a glass rod.

The formula C1_V1=C2_V2 may be applied to any dilution as lengthy as there room at least three recognized variables, and also the early concentration is higher than the last concentration.

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at any time working with hazardous substances, wear proper protective devices to safeguard the eyes and skin. Closed footwear should constantly be worn.

Julie Revel, a previous neurobiologist in pharmaceuticals, started writing professionally in 2009 through a focus on health and an illness prevention. Based in brand-new Jersey, she works as a clinical writer in the healthcare industry. Revel i graduated from drew University with a B.A. In neuroscience and also is currently pursuing her doctor of medical Humanities.