Εξαρταται οπωσδηποτε περισσοτερο απο το πεχα, αλλα οπως ειδες πιο πανω στα παραδειγματα και η θερμοκρασια παιζει το ρολο της.
Υποθετω οτι το τεστ της sera (και νομιζω χωρις να βαζω το χερι μου στη φωτια, οτι το ειχα διαβασει παλιοτερα) οτι οι μετρησεις αυτες αντιστοιχουν σε μια δεδομενη θερμοκρασια 25C, δλδ ενα μεσο ορο θερμοκρασιας στα τροπικα ενυδρεια.
Εδω ομως θελουμε ακριβεια.
Με αμμωνια εχουμε να κανουμε.
Αυτος που εχει χρυσοψαρα θα πανικοβληθει τσαμπα, και αυτος που εχει δισκους θα τους χασει αμεσα, με την ιδια μετρηση.
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Επισης θελει προσοχη στη μετρηση πεχα
Παράθεση:
Temperature has a number of significant effects on pH measurement. Analysts must have an appreciation of these effects so that they can improve and maximise the accuracy of their pH measurements. Automatic Temperature Compensation (ATC) should always be utilised during calibration to correct for the non-Nernstian slope of electrodes. For pH meters that feature automatic buffer recognition, the correct calibration buffers, as specified by the instrument manufacturer, must always be used as the meter has the temperature profile for these buffers stored in memory. Additional sources of error include the calibration isopotential point, thermal or chemical equilibrium effects on the electrode and the temperature coefficient of variation on buffers and samples. To reduce these potential errors, instrument calibration and sample measurement should be performed at the same temperature ideally using a water bath. Also, as the pH of solutions is temperature dependent, the measurement temperature should always be recorded.
Implementation of these simple guidelines will lead to either a reduction or elimination of the problems associated with temperature. This will result in improved accuracy in pH results thus giving the user greater confidence in their pH measurements. Depending on the decisions made based on the pH readings the consequences of inaccurate pH measurement can be more than just a waste of the analysts’ time.
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http://www.reagecon.com/pdf/technica...-_TSP-01-2.pdf