Fermentation

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Q1. Why should a four place analytical balance not be used in weighing a sample if the manual requests only one decimal place accuracy? Ans. We use the analytical balance where we need to weigh the small amount which needs a high degree of accuracy. Whereas, the manual requests only one decimal place accuracy which is not that much important and the time is consumed more to use the analytical balance with four decimal places. Q2. How is the pH meter calibrated?

Ans. Firstly, The pH meter is calibrated by using the two buffer solutions of pH 7.0 and 4.0 which is prepared and placed into small beakers or flasks. After that Rinse the glass electrode with the distilled water using the squeeze bottle and wipe it with the soft tissue paper. Secondly, Switch on the pH meter and place the electrodes into the pH 7.0 buffer solution then correct the pH meter indication and note down the reading after the beep sound comes. Wash down the electrodes with the distilled water using squeeze bottle into an empty beaker and wipe with soft tissue paper. The same process will be followed for the pH 4.0 buffer solution and note down the reading. Q3. How do you clean the glass electrode of the pH meter? Give reasons? Firstly, the electrode is rinsed by the distilled water because the distilled water is very pure in its form and also ion free. Moreover, Any substance or particles which are adhere to the electrode can be washed off with the distilled water. Secondly, after washing the electrode is wiped off by the soft tissue paper because the glass electrode is very sensitive. Also, the water can affect the concentration of the solution being measured which can also results in an error in the measurement. Q4. How is Vaisala probe calibrated?

Ans. The Saturated salt solutions are used to calibrate the Vaisala probe. The results are transferred into the graph and compare with the standard curve and and fix it to compare the values on the standard curve. Hence, the Vaisala probe...
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