pH buffer solutions
PH buffers are water-based chemical solutions made from a weak acid and its salt or a weak base and its conjugated salt. These solutions are resistant to pH changes caused by the addition of small amounts of acid or base, as well as dilution. The above feature has caused these solutions to be used for the calibration of pH measuring devices.
In order to calibrate pH meter devices, it is necessary to use pH buffer solutions with precise numerical values, therefore, Drm produces a variety of acidic, alkaline, and neutral buffer solutions and provides them in suitable packages for its customers.
The most important features of Drm’s Karl Fischer reagents.
- With a certificate of valid analysis and known uncertainty
- Traceable to NIST
- Accurately guarantee the pH of solutions up to 2 decimal places
- Shelf life more than 2 years
- Packaged in polyethylene bottles with the temperature dependence for each buffer listed on it
- The possibility of making pH buffer solutions with numerical values according to the customer’s needs
| buffer | Buffer specifications |
| 4.00 ± 0.04 @ 25 °C | |
| (Potassium hydrogen phthalate) | Traceable in NIST |
| Phosphate buffer | 7.00 ± 0.04 @ 25 °C |
| (KH2PO4/Na2HPO4 ) | Traceable in NIST |
| Borax buffer | 9.00 ± 0.04 @ 25 °C |
| (NaOH/H3BO3) | Traceable in NIST |
| Borax buffer | 10.00 ± 0.04 @ 25 °C |
| (NaOH/H3BO3) | Traceable in NIST |
| problem | the reason | Asymmetric potential | slope | Electrode thrust |
| no problem | Electrode and device both healthy and ideal | |||
| Electrode problem | A crack in the sensitive bulb | |||
| Poisoning of the reference part | ||||
| Short circuit in the electrode wire | ||||
| Old and worn electrode | ||||
| Electrode wire disconnection | ||||
| Electrolyte problem | Contamination or wrong choice of internal electrolyte | |||
| Salt bridge or valve covered by sample sediment | ||||
| Clogging in the electrode | Blocked salt bridge |
