How to prepare your own pH buffers for pH meter calibration from scratch

This video shows you how to prepare pH 4 and pH 7 buffers for pH meter calibration using readily available low cost raw salts. These buffers have a strength of 0.1M. These are the amounts needed to prepare 250mL of buffer solution:

pH 4
Potassium Citrate 2.63g
Citric acid monohydrate 3.45g
(if using anhydrous citric acid, use 3.15g)

pH 7
Potassium Citrate 7.14g
Citric acid monohydrate 0.35g
(if using anhydrous citric acid, use 0.32g)

(Please notice that the Amazon links below are affiliate referral links. This means that if you click on them I may receive a commission from purchases. There is no additional cost to you, but it helps me to keep posting content for free.)

Class A Volumetric Flask (250mL)
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Beaker set
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Scale
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Citric Acid Monohydrate
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Citric Acid (anhydrous)
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Potassium Citrate
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Silicon ice cube trays (similar, but not exact ones shown in video)
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