Steps of use:

According to the volume of the solution to be moved and the requirements to choose the appropriate specifications of the pipette to use, in the titration analysis to accurately move the solution is generally used pipettes, the reaction needs to control the amount of test solution added when the general use of pipettes.

I. Checking the instrument

Check the pipette's mouth and tip for damage, if there is damage, it can not be used;

Wash the instrument

First wash with tap water, soaked with chromic acid washing solution, the operation method is as follows: with the right hand to take the pipette or suction tube at the upper end of the appropriate position, the index finger near the upper mouth of the tube, the middle finger and ring finger open grip on the outside of the pipette, the thumb in the middle of the middle finger and the ring finger in the middle of the position of the inside of the pipette, the pinky finger naturally relaxed; left hand to take the ear washing ball, hold a fist, the suction ear ball in the palm of the hand, the tip of the mouth downward, holding tightly sucking the ear ball, discharge the air inside the ball, will suck the ear ball, and will not use it. The air inside the ball, insert or connect the tip of the ball to the upper port of the pipette (suction tube), taking care that there is no air leakage. Slowly release the fingers of the left hand, slowly inhale the washing liquid into the tube until the part above the scale line, remove the lug ball, quickly block the upper mouth of the pipette (suction tube) with the index finger of the right hand, wait for a few moments, then put the washing liquid back into the original bottle. And use tap water to rinse the inside and outside of the pipette (pipette) until no water beads, and then use distilled water to wash 3 times, control the water and standby.

Aspirate the solution

Shake the solution to be sucked, the solution to be sucked to pour a small portion of a clean and dry small beaker, with filter paper will be cleaned inside and outside the tip of the pipette to absorb water, and inserted into a small beaker to suck the solution, when sucked to the pipette capacity of 1/3, immediately with the right hand forefinger pressed on the mouth of the tube, remove, hold and rotate the pipette, so that the solution flows through the entire inner wall of the tube, will be discharged from the lower end of the tip of the mouth of the solution into the waste cup. The solution can be aspirated after it has been rinsed 3-4 times.

The pipette to be absorbed with the solution to be lubricated with the pipette to be sucked under the surface of 1 ~ 2cm with the suction lug ball according to the above method of operation to suck the solution (note that the pipette inserted into the solution can not be too deep, and to be sucked downward insertion, always maintain this depth). When the liquid level in the tube rises to about 1~2cm above the standard line, quickly block the mouth of the tube with the right index finger (at this time, if the solution falls below the standard line, it should be reabsorbed), raise the pipette to be sucked up to the surface of the liquid and make the tip of the tube to contact the inner wall of the container to be sucked up for a few moments after lifting it up, and wipe the small amount of solution adhering to the lower end of the pipette or suction tube dry with filter paper. (When moving the pipette or suction tube, keep the pipette or suction tube vertical and not tilted.)