How to calibrate your pH electrode

Рет қаралды 8,471

Күн бұрын

In this video, we show you how to calibrate a pH electrode on a 913 pH/DO Meter or 914 pH/Conductometer. Calibration of your pH electrodes is essential for accurate pH measurements.
You will learn:
- how often you should calibrate your electrode,
- which material you need for the calibration,
- how to set the parameters for the calibration on the meter,
- how many buffers you should use,
- and why you need to measure the temperature during calibration.
Find more tips and tricks for pH measurements on our blog:
FAQ: All about pH calibration: www.metrohm.com/en/discover/b...
Avoiding the most common mistakes in pH measurement: www.metrohm.com/en/discover/b...
0:00 Introduction
0:27 Calibration frequency
1:07 Material needed for calibration
1:45 Preparations for the calibration
2:22 Settings on the meter
2:38 How many buffers should you use
2:55 Selection of buffer type
3:03 Start calibration
3:36: Effect of temperature on calibration
3:55 Continuation of calibration
5:08 After the calibration

Пікірлер: 32

@refar1624 4 ай бұрын

Muy buen video y lo explica muy bien.

@RobIncFilmsWeddings Жыл бұрын

Thank you for running over the basics of pH calibration and a reminder to calibrate more often to ensure consistent sample accuracy!

@MetrohmTV Жыл бұрын

Glad it was helpful!

@RobIncFilmsWeddings 11 ай бұрын

@@MetrohmTV Is it still advisable to use pH 9 buffer for calibration bracketing samples with expected higher pH values, even though alkaline buffers have a high CO2 uptake?

@MetrohmTV 11 ай бұрын

For precise pH measurement results, we always recommend a multi-point calibration. The pH of the sample should always be within the pH range of the buffers that are used for calibration to minimize errors. So, if you are expecting higher pH values (e.g., pH 8) the use of pH buffer 9 is advisable. To avoid a carbon dioxide uptake of buffers with higher pH values, always use fresh buffer solutions. Our buffer solutions in single use sachets are quite suitable for this. If you have more questions on pH measurement and calibration please have a look at our current monograph “pH-measurement - everything from A-Z including best practices and examples”: www.metrohm.com/en/products/8/1085/81085081.html

@prashantpatil5766 Жыл бұрын

Thanks for the detailed calibration video.

@MetrohmTV Жыл бұрын

You're welcome!

@Radhe_Tyagi Ай бұрын

Nice video...

@MetrohmTV Ай бұрын

Thanks!

@gidissadeksissa2219 10 ай бұрын

thank you for the detailed explanation Addition of NaOH or HCl to adjust the PH of a solution does not affect the initial concentration of a solution?

@MetrohmTV 10 ай бұрын

Hi gidissadeksissa2219 Do you mean the initial concentration of an analyte? The initial concentration of an analyte is not affected if the analyte is sodium, hydroxide, hydronium, or chloride. Does this answer your question, or did we misunderstand it? Best regards Metrohm International Headquarters

@bhagyaranasingha2216 4 ай бұрын

Nice explanation 👌

@MetrohmTV 4 ай бұрын

Thank you 🙂

@kirankumargarud2800 11 ай бұрын

Is it necessary to maintain the buffer temperature externally at exact 25 degree celcious during calibration and sample pH measurment as well

@MetrohmTV 11 ай бұрын

Since temperature has an impact on your pH measurement (Nernst equation), calibration and pH measurement should be performed at the same temperature, e.g., at 25 °C. For further information please read our blog post “How temperature influences the pH value”: www.metrohm.com/en/discover/blog/2023/how-temperature-influences-the-ph-value.html

@samueltinku250 8 ай бұрын

Great video 😊! Why only 4,7,9 buffers used for calibration! What is the maximum limit can dip the ph electrode or need to only dip the end of the electrode

@MetrohmTV 8 ай бұрын

Hi Samuel Thank you for your comment. You always have to calibrate with buffers which lie within your measuring range. With buffers pH 4, 7, and 9, you’re already covering quite a broad pH range. Should you need to cover an even broader range, you can use pH buffers from other manufacturers. As for the electrode: The electrode has to be dipped in in such a way that the diaphragm is fully covered by your measuring solution. I.e., the glass membrane and diaphragm have to be immersed but the electrolyte filling hole has to stay above the sample. Best regards Michel, Metrohm International Headquarters

@samueltinku250 8 ай бұрын

@@MetrohmTV 😀 thanks for your reply 😊

@akakisimonishvili7471 3 ай бұрын

Hello, I have a new HACH PHC101 electrode, but I can not calibrate, it says (standard not recognized. Rinse the electrode and repeat). Can you help me and tell me the reason?

@MetrohmTV 3 ай бұрын

Hi Thank you for your comment. Could you please check if another electrode can be calibrated? This way we would know if the problem lies with the instrument or the sensor. In general, if you require instrument support, please contact your local Metrohm organization or exclusive distributor. BR Michel, Metrohm International Headquarters

@tnktxn640 12 күн бұрын

Why do I have to calibrate more often when performed at high temperatures? If I do it at 28 degrees Celsius, is calibration necessary every day?

@MetrohmTV 11 күн бұрын

We would recommend calibrating the sensor daily and at the temperature of the samples for exact results. It depends a bit on the accuracy that is required.

@iviaggidiAntony Жыл бұрын

I always use three buffer : pH 4 - 7 - 9

@MetrohmTV Жыл бұрын

That's exactly the right way to do it!😊

@changyongkang252 9 ай бұрын

Why the calibrate during first buffer taking much, sometimes wait around 45 minute still cannot proceed to next buffer

@MetrohmTV 9 ай бұрын

Hi Thank you for your comment. Typically, a buffer measurement should not take more than a few seconds or a few minutes at most. A measuring time of 45 minutes is a clear indicator that something is not right, the most obvious candidate being a defective electrode. Please check whether your electrode needs to be replaced or contact your local Metrohm organization if you need technical support: www.metrohm.com/en.html#country-selection Best regards Metrohm International Headquarters

@farooqarshad5962 11 ай бұрын

What is ideal slope value after pH calibration.

@MetrohmTV 11 ай бұрын

The electrode slope is given by the Nernst equation and is 0.059 V per pH 1 at 25 °C. These are ideal values from which new Metrohm pH electrodes only differ slightly. The electrode zero point is ± 0.015 V. But please be aware that the electrode zero point and the electrode slope may change as a result of the aging of the glass membrane or changes (e.g., contamination) on the diaphragm. For more information on this topic, please read our blog “FAQ: All about pH calibration”: www.metrohm.com/en/discover/blog/20-21/faq--all-about-ph-calibration.html And our our application bulletin AB-188 “pH measurement technique”: www.metrohm.com/en/applications/ab-application-bulletins/ab-188.html

@srilatasampath9883 10 ай бұрын

Where do we store the buffer solution if we are not making fresh everyday

@MetrohmTV 10 ай бұрын

Hi Buffer sachets are for single use only. Metrohm buffers in the bottle last up to 3 months after opening and are easy to store on shelves. After a calibration, the buffer should be discarded and should not be reused. You can find more information in this blog post: www.metrohm.com/en/discover/blog/20-21/faq--all-about-ph-calibration.html

@ericksanchezperez829 3 ай бұрын

What is the problem when the slope is Less than 97%? And pH(0) is higger than 7.10?

@MetrohmTV 3 ай бұрын

Hi Erick There could be various reasons for this. You can find additional information on this topic in our Application Bulletin AB-188: www.metrohm.com/en/applications/ab-application-bulletins/ab-188.html If you need to troubleshoot your instrument or sensor, please get in touch with your local Metrohm subsidiary or exclusive distributor: www.metrohm.com/en.html#country-selection BR Michel, Metrohm International Headquarters