Vernier Tech Info Library TIL #369

Question

Where do I get pH Storage Solution? (Buffer Storage Solution)

Answer

We carry pH Storage Solution with buffer preservative (mold inhibitor) added. Each bottle contains 500 mL of pH Storage Solution We sell this as: pH Storage Solution, order code PH-SS, $15.00.

If you wish to prepare your own storage solution, you can do so by adding 10g of solid potassium chloride (KCl) to 100 mL of a buffer pH 4 solution. It is a good idea to add some buffer preservative (mold inhibitor), as well (add 3 drops preservative/100 mLs solution). The preservative can be purchased from Flinn Scientific (1-800-452-1261) if needed (order code BO175, 60-mL bottle).

We currently ship our electrodes in a buffer storage solution that already has Buffer Preservative added to it. Our pH Buffer Capsules kit (order code PHB) includes 4 capsules of pH 4, 7, and 10 buffer along with a bottle of preservative. If you don't have buffer tablets to prepare a buffer pH 4, you can prepare your own using the following recipe: Add 2.0 mL of 0.1 M HCl to 1000 mL of 0.1 M potassium hydrogen phthalate.

Created by: dholmquist on August 06 1998
Last updated by: jhopkins on January 18 2007