Why does water bubble up in a plastic bottle?

What kind of water are you talking about? tap water drinking distilled? Tap water has carbonic acid, that is just CO2 that is dissolved in the water. If you de-gas the water there may be less bubbles. read more

Hey water bubble up in a plastic Bottle because. the dissolved gases such as oxygen come out of the water when it is stationary for some time, hence bubbles start forming. It is just like a soda bottle foaming up, Many people here have mentioned chlorine, but it is not only because of chlorine. read more

Water in PET bottles are generally safe to drink. If stored above 60C(140F) for 2 weeks, the antimony used in many PET bottles will leach into the water to levels that exceed EU standards. In most of the first world, this is not much of a problem. Glass bottles also leach significant chemicals into the water at higher temperatures. read more

The plastic bottle isn't perfectly smooth. There are microscopic pockets of air along the walls of the bottle. As bubbles form, they attract each other, Sort of like watching water roll down the window on a rainy day. So the question isn't necessarily why the are attracted to the walls, but what keeps the air in place along the walls of the bottle. read more

Plastics bottles are made by a process called Blow-molding(HDPE, PP) or Stretch Blow-molding(PET). During the blow molding process the material is heated and stretched along length and width(bidirectional) using air. read more