Final answer:
The technique of inserting air into the vial to allow solution to enter the syringe is known as the air exchange technique, essential for maintaining sterility in laboratory procedures.
Step-by-step explanation:
The technique described is achieved by inserting a small amount of air into the vial a little at a time and allowing solution to enter the syringe. This is known as the air exchange technique. By holding tubes or bottles at an angle during the transfer process and using a flame to discourage contaminants, along with practicing pipette handling with aseptic techniques, one can ensure precise and contamination-free laboratory procedures. The air exchange technique is crucial in laboratory settings where maintaining sterility and accuracy in measuring and transferring liquids is necessary.