How to Make Chemical Solutions
Define a percent by weight/volume solution., Identify the volume of solution you want to make., Calculate the number of grams needed to make the solution., Weigh out the mass of the compound., Dilute the compound in the necessary amount of solvents.
Step-by-Step Guide
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Step 1: Define a percent by weight/volume solution.
A percent solution simply means parts per hundred.
In terms of making a chemical solution this means that you will have 1 gram of compound for every 100 milliliters of liquid or 1 mL/100mL if you are working with an already liquid compound.For example by weight:
A 10% solution by weight simply means that you have 10 grams of compound dissolved in 100 mL of solution.
For example by volume:
A 23% solution by volume simply means that you have 23 mL of liquid compound in every 100 mL of solution. -
Step 2: Identify the volume of solution you want to make.
In order to determine the mass of the compound needed, you must first determine the final volume of the solution you want to make.
The volume will be determined by how much solution you need for your task, how frequently you will need it, and the stability of the solution over time.
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. , To calculate the number of grams needed to make your percent solution, you will multiply using the formula: # grams = (percent desired)(desired volume/100 mLs).
The percent desired will be expressed in grams and the desired volume must be expressed in milliliters.For example:
Make a 5% solution of NaCl in 500 mL of water. # grams = (5g)(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: 25 mL of NaCl into 475 mL of water. , Once you have calculated the desired mass, you need to weigh it out.
Using a calibrated balance, place a weighing dish and zero it out.
Weigh out the necessary amount of compound in grams and set it aside.
Always clean the balance of any powder before continuing to make the solution.
For example:
Weigh out 25 g of NaCl. , Unless otherwise stated, you will probably be diluting the compound in water.
Using a graduated cylinder (a measuring device used specifically for volume), measure out the desired amount of liquid.
Mix with powdered compound until dissolved.Clearly label the container with both the chemical and the concentration.
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. -
Step 3: Calculate the number of grams needed to make the solution.
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Step 4: Weigh out the mass of the compound.
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Step 5: Dilute the compound in the necessary amount of solvents.
Detailed Guide
A percent solution simply means parts per hundred.
In terms of making a chemical solution this means that you will have 1 gram of compound for every 100 milliliters of liquid or 1 mL/100mL if you are working with an already liquid compound.For example by weight:
A 10% solution by weight simply means that you have 10 grams of compound dissolved in 100 mL of solution.
For example by volume:
A 23% solution by volume simply means that you have 23 mL of liquid compound in every 100 mL of solution.
In order to determine the mass of the compound needed, you must first determine the final volume of the solution you want to make.
The volume will be determined by how much solution you need for your task, how frequently you will need it, and the stability of the solution over time.
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. , To calculate the number of grams needed to make your percent solution, you will multiply using the formula: # grams = (percent desired)(desired volume/100 mLs).
The percent desired will be expressed in grams and the desired volume must be expressed in milliliters.For example:
Make a 5% solution of NaCl in 500 mL of water. # grams = (5g)(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: 25 mL of NaCl into 475 mL of water. , Once you have calculated the desired mass, you need to weigh it out.
Using a calibrated balance, place a weighing dish and zero it out.
Weigh out the necessary amount of compound in grams and set it aside.
Always clean the balance of any powder before continuing to make the solution.
For example:
Weigh out 25 g of NaCl. , Unless otherwise stated, you will probably be diluting the compound in water.
Using a graduated cylinder (a measuring device used specifically for volume), measure out the desired amount of liquid.
Mix with powdered compound until dissolved.Clearly label the container with both the chemical and the concentration.
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.
About the Author
Amy Knight
Writer and educator with a focus on practical organization knowledge.
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