Potassium Nitrate Dissolution

How to Use

Controlling the temperature of the required saturated solution is another key aspect of this experiment, as the potassium nitrate dissolution is greatly affected by temperature. In addition, with general thermometers and accuracy calibration (especially distiller's grains thermometers), a temperature of two or three degrees above or below is sufficient to affect the calculation results.

(1) So during the experiment, it is advisable to calibrate the thermometer, preferably to identify any errors in the thermometer.

(2) According to the heat absorption properties of nitric acid bait dissolved in water, it can be directly dissolved to prepare a saturated solution at lower temperatures in winter at low room temperature (we tested using 10 milliliters of distilled water at a water temperature of 15 tons). Dissolve nitric acid eggs in the medium and obtain a saturated solution at a temperature of about

Pay Attention

When potassium nitrate dissolution occurs, what attention should be paid to

(1) except for measuring at lower temperatures. At other temperatures, the water temperature in the test tube should reach the desired temperature and remain constant before adding KN0 crystals and stirring with a glass rod.

(2) Note that after potassium nitrate dissolution, it is necessary to let it stand for a few minutes to ensure that the dissolution equilibrium is reached before pouring the solution. And pay attention to controlling the temperature at the measured temperature during the standing time.

(3) Tell students not to stir with a thermometer, and it is best not to insert the thermometer into the remaining crystals for temperature measurement.

(4) When measuring the temperature above room temperature, as soon as the test tube leaves the water bath, the temperature immediately drops and crystallization occurs. Therefore, the pouring action of the solution should be fast to avoid excessive temperature differences between the poured liquid and the original solution.

(5) The diameter of the trial tube used should be larger, and the test tube should not be too long. The first issue of '1978 Shenxue Technology' suggests using a 100-ml beaker to hold a water bath. We feel that using a small beaker for water bath operation is not convenient, and the effect is not ideal due to the difficulty in insulating the water bath using a small beaker.