How to stop a serial bubbling?

Generating bubbles by injecting air slowly with a syringe in a quiescent liquid is a standard process. However, the experiment shows that the generation of a single bubble can be a challenge as a train of bubbles is often observed even at very slow injection rate. Here, we explore the different regimes of bubble generation experimentally. We also model the situation through direct numerical simulations, which reproduce and extend the experimental measurements. We rationalize the observation of the serial bubbling with a thermodynamic model and highlight the different regimes. The serial bubbling can be a problem in some applications, but its understanding can also be leveraged to deliver a given number of bubbles.