Answer:
Muscular contractions that moves food along the digestive tract.
Anions are negative ions so it’s when an atom gains electrons
Helium is a chemical element of the atomic number 2, an inert gas that is the lightest member of the noble gas series.
These means, Helium is lighter than air, and for this is why all other balloons may not float.
The helium balloon displaces an amount of air (Just like an empty water bottle displaces an amount of water). As long as the weight of the helium plus the balloon fabric is lighter than the air displaces, the balloon will float in the air.
I'm pretty sure it would make it unstable, hydrogen only has one proton thus having the ability to stabilize one electron, adding another electron would most likely make the atom reactive to any positively charged atom to loose this extra electron.
