For an example by volume: A 23% solution by volume simply means that you have 23 mL of liquid compound in every 100 mL of solution.

For example: Make a 5% solution of NaCl in 500 mL of water. Make only the amount you need if the solution must be made fresh every time it is used. If the solution is stable long-term, you can make a larger volume to store and use later.

For example: Make a 5% solution of NaCl in 500 mL of water.

grams = (5)(500mL/100mL) = 25 grams If the NaCl was already dissolved in liquid form, you would add 25 mL of NaCl instead of grams of powder and subtract that volume from the final volume, i.

e. 25 mL of NaCl into 475 mL of water.

For example: Weigh out 25 g of NaCl. Always clean the balance of any powder before continuing to make the solution.

For example: Mix 500 mL of water and 25 g of NaCl to make a 5% solution. Remember, if you’re diluting a liquid compound, you must subtract out the volume of liquid being added from the final volume: 500 mL – 25 mL = 475 mL of water. Clearly label the container with both the chemical and the concentration.

For example: The formula weight of sodium chloride (NaCl) 58. 44 g/mol. The formula weight of a compound is the mass in grams of one mole of the compound.

For example: Make a 50 mL solution of 0. 75 molar NaCl. To convert mL to L, divide by 1000: 0. 05 L.

For example: If you want to make 50 mL of a 0. 75 molar solution of NaCl (FW: 58. 44 g/mol), you can calculate the number of grams of NaCl needed.

grams = 0.

05 L * 0. 75 mol/L * 58. 44 g/mol = 2. 19 grams NaCl. When you cancel all units, you should be left with grams of the compound.

For example: Weigh out 2. 19 grams of NaCl. Clean the balance when you are finished using it.

For example: Using a graduated cylinder (measuring equipment for volume), measure 50 mL of water and mix it with the 2. 19 g of NaCl. Mix until the powder is fully dissolved. Clearly label the solution with the molarity and the compound so it can be easily identified in the future.

For example: Make 75 mLs of a 1. 5 M stock of NaCl from a working stock of 5 M. The working stock is at a concentration of 5 M and you want to dilute to a final concentration of 1. 5 M.

For example: Make 75 mLs of a 1. 5 M stock of NaCl from a working stock of 5 M.

For example: Make 75 mLs of a 1. 5 M stock of NaCl from a working stock of 5 M. To calculate the volume of the working stock needed, the equation gets rearranged to solve for V1: V1 = (V2C2)/C1 V1 = (V2C2)/C1 = (0. 075 L * 1. 5 M)/5M = 0. 0225 L. Convert L back to mL by multiplying by 1000: 22. 5 mL.

For example: You want a final volume of 75 mLs and will be adding 22. 5 mL of the stock solution. Therefore, 75 – 22. 5 = 52. 5 mLs. This volume is the amount of dilution solution you will use.

For example: Measure 22. 5 mLs of the stock 5 M solution of NaCl and dilute it with 52. 5 mLs of water. Stir to mix. Label the container with both the concentration and the compound: 1. 5 M NaCl. Remember, if you are diluting an acid with water, always add the acid to the water.

Wear a lab coat that is made of an inflammable material. Eye protection should have side shields to protect from splashes across the face.

Refresh your memory with the proper safety precautions every time you work with acids.